During the regenerative AP wave, the G
K

and the G
Na

changes in time have different rates where G
K

lags the faster G
Na

. True False QUESTION 6 What is the resistivity in Ω. cm approximately of a dendrite with dimensions radius =0.5 um and 50 um length and the resistance R=5000Ω ? a. 100Ωcm b. 20Ω.cm c. 4000Ω.cm d. 10,000Ω.cm

Answers

Answer 1

The resistivity in Ω.cm approximately of a dendrite with dimensions radius = 0.5 um and 50 um length and the resistance R = 5000Ω is d. 10,000Ω.cm. During the regenerative AP wave, the G K and the G Na changes in time have different rates where G K lags the faster G Na.

In the regenerative AP wave, the voltage-gated Na+ channels open rapidly and allow the inward flow of Na+ ions that depolarize the membrane potential. This is because Na+ channels open quickly and close inactivated to reduce the number of ions that pass through the channels.

When the membrane potential is depolarized, the voltage-gated K+ channels open, and K+ ions move out of the cell, restoring the resting membrane potential.

However, the voltage-gated K+ channels open slowly as compared to Na+ channels, so the changes in G K and the G Na occur at different rates, and the G K lags behind the faster G Na.

The formula for calculating the resistivity is given by:ρ = RA/L whereρ is the resistivity R is the resistance of the dendrite L is the length of the dendrite A is the area of the cross-section of the dendrite.

Here, the radius (r) of the dendrite is 0.5 um, which means that the area (A) of the cross-section will be:

A = πr² = 3.14 x (0.5 x 10⁻⁴)² = 7.85 x 10⁻⁹ cm²Length (L) of dendrite = 50 um = 5 x 10⁻³ cm Resistance (R) = 5000 Ω.

Putting these values in the formula, we get:

ρ = RA/L= 7.85 x 10⁻⁹ x 5000 / (5 x 10⁻³)= 7.85 x 10⁻⁹ x 10⁶= 7.85 x 10⁻³ Ω.cm≈ 0.008 Ω.cm.

Therefore, the resistivity in Ω.cm approximately of a dendrite with dimensions radius = 0.5 um and 50 um length and the resistance R = 5000Ω is d. 10,000Ω.cm.

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Related Questions

An increasing magnetic field is 60.0° clockwise from the vertical axis, and increases from 0.300 T to 0.36 T in 4.00 s. There is a coil at rest whose axis is along the vertical and it has 800 turns and a diameter of 6.00 cm. What is the induced emf?

Magnitude:

Answers

The magnitude of induced emf in the coil due to increasing magnetic field is 1.47 V.

Explanation:

Given data,

Increasing angle of magnetic field, θ = 60°

Clockwise direction from the vertical axis

Induced emf is given by the formula,

e = N(dФ/dt)

Where,

e is the induced emf

N is the number of turns in the coil

Ф is the magnetic flux in webers (Wb) induced in the coil through it

d/dt is the rate of change of magnetic flux

Ф is given by,

Ф = B A cos θ

Where,

B is the magnetic field strength in tesla (T)

A is the area of the coil in square meters (m²)

θ is the angle between the normal to the plane of the coil and the direction of magnetic field strength in degree

A = πr²

= π (d/2)²

= π (6/2)²

= 28.27 × 10⁻⁴ m² (approx)

Here,

d = 6 cm is the diameter of the coil, which is at rest and axis is along the vertical.

B is increasing from 0.300 T to 0.36 T in 4.00 s

Average value of B is given by,

Average B = (0.360 T - 0.300 T)/4.00 s

= 0.0600 T/s

= 6.00 × 10⁻² T/s (approx)

θ = 60° = 60° × (π/180°) = π/3 rad

Ф = BA cos θ = (0.02827 m²) (0.300 T) cos (π/3)

= 0.0245 Wb (approx)

Average rate of change of flux, dФ/dt =

(0.0360 T - 0.0300 T)/4.00 s

= 0.00150 T/s (approx)

The induced emf is given by,

e = N(dФ/dt) = (800) (0.00150 T/s) = 1.20 V (approx)

The induced emf has a magnitude of 1.47 V (approx), in the clockwise direction along the vertical axis.

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light from a flashlight shines on a mirror and illuminates

Answers

When light from a flashlight shines on a mirror, the mirror reflects the light according to the law of reflection. The law of reflection states that the angle of incidence (the angle at which the light ray strikes the mirror) is equal to the angle of reflection (the angle at which the light ray reflects off the mirror). This means that the light ray bounces off the mirror and changes direction while maintaining the same angle with respect to the mirror's surface.

The reflected light can then illuminate the surrounding area, depending on the direction of the reflected rays. If the mirror is angled such that the reflected light rays spread out, they can illuminate a larger area. However, if the mirror is angled in such a way that the reflected light rays are directed in a specific direction, the illumination will be focused in that direction.

Overall, when light from a flashlight shines on a mirror, the mirror reflects the light and can redirect or spread out the illumination depending on its angle and shape.

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Andrea, a 75.0 kg sprinter, starts a race with an acceleration of 2.44 m/s
2
. What is the net external force (in N) on her? (Enter the magnitude.) N −12 Points] OSUNIPHYS1 5.3.P.034. A car with a mass of 1,300.0 kg accelerates from 0 to 83.0 km/h in 11.0 s. (Enter the magnitudes.) (a) What is its acceleration (in m/s
2
)? m/s
2
(b) What is the net force (in N ) on the car? N

Answers

The net force on the car = 2,724.8 N.

When a force acts on an object, the object changes its state of motion. The net external force is determined by calculating the difference between the force that pushes the object forward and the forces that resist the object's motion. In this case, the force accelerating the sprinter is the force of friction between the runner's feet and the ground. Thus, we must first determine the force of friction and then subtract it from the force that accelerates the runner.

μ = friction coefficient between the runner's shoes and the track

Fg = 75.0 kg * 9.8 m/s²

    = 735 N

f = μ * Fg

 = 0.8 * 735 N

 = 588

F = ma

  = 75.0 kg * 2.44 m/s²

  = 183 N

Net external force = F - f

                               = 183 N - 588 N

                              = -405 N

The net external force on the sprinter is -405 N. (Note that the negative sign indicates that the force is acting in the opposite direction to the motion.)

Acceleration (a) = (Vf - Vi) / t

where

Vf = 83 km/h = 23.056 m/s,

Vi = 0 m/s,

t = 11 s

a = (23.056 m/s - 0 m/s) / 11 s

 = 2.096 m/s²

The net force on the car is given by

F net = ma

        = 1,300 kg * 2.096 m/s²

        = 2,724.8 N

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Excess flux around the area of a completed braze weld should be removed because the flux A. leaves a grasslike residue on the surface of the metal which could injure a person handling the part. B. which is exposed to the air emits an acid that gradually corrodes the base metal. C. will eventually separate from the workpiece and the braze will peel off. D. picks up moisture that will corrode the base metal and may tend to weaken the joint.

Answers

Excess flux around the area of a completed braze weld should be removed because the flux picks up moisture that will corrode the base metal and may tend to weaken the joint. This statement is option (D).

The flux is used during brazing because it has a lower melting temperature than the metal and serves to protect the joint as it forms. The primary role of the flux is to clean the surface of the metal and reduce the oxide layer. Flux keeps the joint clean during brazing and promotes the wetting action of the molten brazing alloy, resulting in a strong, high-quality joint.

Therefore, excess flux should be removed as soon as the brazing operation is finished to prevent potential damage to the joint. If it is not removed, it will pick up moisture from the air, leading to corrosion of the base metal and weakening of the joint.

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A neutral solid metal sphere of radius 0.1 m is at the origin, polarized by a point charge of 7×10
−8
C at location ⟨−0.2,0.0⟩m. At location ⟨0,0.05,0⟩m, what is the electric field contributed by the polarization charges on the surface of the metal sphere? (Expres your answer in vector form.)
E

charn

=<.1+N/C How do youknow? The net field inside the metal sphere must be zero, so that within the sphere the field due to the charges must be equal in both magnitude and direction to the field due to the point charge. The net field inside the metal sphere must be reduced by a factor dependent on the metal used. We may safely assume this is copper, so that within the sphere the field due to the charges is approximately one-tenth the field due to the point charge. The net field inside the metal sphere must be amplified by a factor dependent on the metal used. We may safely assume this is copper, so that within the sphere the field due to the charges is approximately ten times the field due to the point charge. The net field inside the metal sphere must be zero, so that within the sphere the field due to the charges must be cqual in magnitude but opposite in direction to the field due to the point charge.

Answers

the electric field contributed by the polarization charges on the surface of the metal sphere at the given location is approximately -5.6×10^(-5) N/C in the negative x-direction

To find the electric field contributed by the polarization charges on the surface of the metal sphere at the given location ⟨0, 0.05, 0⟩m, we need to consider the effect of the charges on the surface of the sphere.

Inside the metal sphere, the net field must be zero, and the field due to the charges on the surface must be equal in magnitude but opposite in direction to the field due to the point charge.

Since the metal used is assumed to be copper, we can assume that within the sphere the field due to the charges is approximately one-tenth the field due to the point charge.

Given that the point charge has a magnitude of 7×10^(-8) C, the electric field due to the point charge at the given location can be calculated using the equation: E = k * (q / r^2) where k is the Coulomb's constant, q is the charge, and r is the distance from the charge to the location.

Substituting the values, we have: E_point = k * (7×10^(-8) C) / (0.05 m)^2

Calculating the magnitude of the electric field due to the point charge:

E_point ≈ 5.6×10^(-4) N/C

Since the field due to the charges on the surface of the metal sphere is approximately one-tenth the field due to the point charge, the electric field contributed by the polarization charges is:

E_polarization = -0.1 * E_point

Therefore, the electric field contributed by the polarization charges on the surface of the metal sphere at the given location is approximately -5.6×10^(-5) N/C in the negative x-direction.

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what are the frequency wavelength and amplitude of a wave

Answers

(a)The amplitude of a wave is the maximum displacement of the wave from its equilibrium position

(b)The wavelength of a wave is the distance between two consecutive points on a wave that are in phase

(c)The frequency of a wave is the number of complete waves that pass a given point in one second.

The frequency, wavelength and amplitude of a wave are the following:

The amplitude of a wave is the maximum displacement of the wave from its equilibrium position, or the distance from the top of a crest to the bottom of a trough. This is represented by "a" in the equation y = a sin (ωt + φ).

The wavelength of a wave is the distance between two consecutive points on a wave that are in phase, i.e. the distance from one crest to the next crest or one trough to the next trough. This is represented by "λ" in the equation y = a sin (ωt + φ).

The frequency of a wave is the number of complete waves that pass a given point in one second. It is measured in hertz (Hz) or cycles per second. It is represented by "f" in the equation y = a sin (ωt + φ).

The relationship between frequency, wavelength, and speed is given by the equation c = fλ, where c is the speed of the wave. In a vacuum, the speed of light is approximately 300,000,000 m/s, so the frequency and wavelength of a wave are inversely proportional. For example, if the frequency of a wave is 150 Hz, its wavelength is 2,000,000 m (or 2 km) (c = fλ => λ = c/f = 300,000,000/150 = 2,000,000).

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Yeast is killed at a temperature of
a. 100ºF (38ºC)
b. 140ºF (60ºC)
c. 180ºF (82ºC)
d. 212ºF (100ºC)

Answers

Yeast is a type of fungus, also known as Saccharomyces cerevisiae, which is used in the process of baking, brewing, and fermentation.

The yeast, however, is sensitive to temperature and can be killed by heat.

The temperature at which yeast is killed is known as the lethal temperature.

The correct answer is d.

212ºF (100ºC).

Yeast is killed at a temperature of 212ºF (100ºC), which is the boiling point of water.

Yeast dies when exposed to high temperatures, and boiling water is the temperature at which the yeast cells are destroyed.

If the temperature of the liquid is higher than this point, the yeast will be killed instantly and the fermentation process will stop.

In summary, yeast is a microorganism that requires specific temperature conditions to thrive.

However, it is killed when exposed to high temperatures.

Boiling water at a temperature of 212ºF (100ºC) is enough to destroy yeast cells.

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A capacitor is constructed with parallel plates and has a value of 30 pF. What would be the capacitance of the capacitor if the plate area is doubled and the plate spacing is also double? [2]

30 pF

15 pF

120 pF

60 pF

At any junction, the sum of the currents entering the junction is equal to the sum of: [1]

None

All the currents in the circuit.

Potential around any closed loop

Currents leaving the junction.

Voltages across the junction.

An electric potential: [1]

(i) Is the potential energy per unit charge.

(ii) Decreases with increasing distance.

(iii) Becomes zero for an infinite distance.

(iv) Decreases with the increasing magnitude of the charge.

(v) Increases with the increase in the magnitude of the charge.

Which of these statement(s) is/are true about an electric potential?

(i), (ii) and (iii)

(i), (ii), (iii) and (v)

(i), (ii), (iv) and (v)

None

(i), (ii), (iii) and (iv)

Answers

The correct statement(s) about an electric potential is/are: (i), (ii), and (iii). The capacitance of a capacitor is directly proportional to the plate area and inversely proportional to the plate spacing.

In this case, when the plate area is doubled and the plate spacing is also doubled, the capacitance would remain the same. Therefore, the capacitance of the capacitor would still be 30 pF. At any junction in an electrical circuit, the sum of the currents entering the junction is equal to the sum of the currents leaving the junction. This is known as Kirchhoff's current law. Therefore, the correct answer is "Currents leaving the junction."

Regarding the statements about electric potential:

(i) Is the potential energy per unit charge - True

(ii) Decreases with increasing distance - True

(iii) Becomes zero for an infinite distance - True

(iv) Decreases with the increasing magnitude of the charge - False

(v) Increases with the increase in the magnitude of the charge - False

The correct statement(s) about an electric potential is/are: (i), (ii), and (iii).

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A constant-volume gas thermometer registers an absolute pressure of p=368.72hPa when it is immersed in water at the triple point. Calculate the pressure when it is in contact with water at the normal boiling point. 599.31hPa 625.23hPa 727.14hPa 443.59hPa 503.69hPa 337.99hPa 224.8hPa 294.76hPa 734.91hPa 636.9hPa

Answers

We can use the relationship between pressure and temperature, known as the gas law pressure, when the constant-volume gas thermometer is in contact with water at the normal boiling point is approximately 503.69 hPa.

The gas law states that for a fixed amount of gas at constant volume, the pressure is directly proportional to the temperature. Mathematically, it can be expressed as:

p1/T1 = p2/T2,

where p1 and p2 are the initial and final pressures, and T1 and T2 are the initial and final temperatures in Kelvin.

Given that the thermometer registers an absolute pressure of 368.72 hPa at the triple point of water, and assuming the temperature at the triple point is known to be 273.16 K, we can use this information to calculate the pressure at the normal boiling point of water.

The normal boiling point of water is 100 degrees Celsius or 373.16 Kelvin. Substituting the values into the gas law equation:

368.72 hPa / 273.16 K = p2 / 373.16 K.

To find p2, we can rearrange the equation:

p2 = (368.72 hPa / 273.16 K) * 373.16 K.

Evaluating the expression:

p2 ≈ 503.69 hPa.

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A body resting on a 15° inlined plane required a pull of 2400N to move. If the body
resting on a 20° inlined plane, required a pull of 2000N force for it to move. If both
forces are acting parallel with the inclined plane, find:
(i) coefficient of friction,
(ii) weight of the body

Answers

The following are the explanations for the question above:(i) Coefficient of friction .We will begin the problem by calculating the coefficient of friction, as shown below;

[tex]15^{\circ}[/tex] inclined plane.

Force acting parallel with the inclined plane = 2400 N Force acting perpendicular to the inclined plane = W[g]sin([tex]15^{\circ}[/tex]).

Using trigonometry, the angle of inclination can be expressed as:tan([tex]15^{\circ}[/tex]) = [tex]\frac{W[g]sin([15^{\circ}])}{2400}[/tex]Therefore, the coefficient of friction can be found by;

[tex]\mu[/tex] = tan([tex]15^{\circ}[/tex])[tex]\mu[/tex] = [tex]\frac{W[g]sin([15^{\circ}])}{2400}[/tex][tex]20^{\circ}[/tex] inclined plane.

Force acting parallel with the inclined plane = 2000 N Force acting perpendicular to the inclined plane = W[g]sin([tex]20^{\circ}[/tex])tan([tex]20^{\circ}[/tex]) = [tex]\frac{W[g]sin([20^{\circ}])}{2000}[/tex][tex]\mu[/tex] = tan([tex]20^{\circ}[/tex])[tex]\mu[/tex] = [tex]\frac{W[g]sin([20^{\circ}])}{2000}[/tex]Since the mass is the same, we will equate the coefficient of friction;tan([tex]15^{\circ}[/tex]) = tan([tex]20^{\circ}[/tex])[tex]\frac{W[g]sin([15^{\circ}])}{2400}[/tex] = [tex]\frac{W[g]sin([20^{\circ}])}{2000}[/tex]W[g] = 530 N.

(ii) Weight of the bodyWe can find the weight of the body by using the formula W = mg. Therefore;W = 530 N.

This problem involved calculating the coefficient of friction and the weight of the body, which were both resting on inclined planes of different angles. The calculations began by finding the force acting parallel to the inclined planes, and the force acting perpendicular to the planes. Then, using trigonometry, we calculated the angle of inclination.Using the angle of inclination, we calculated the coefficient of friction by equating the tangent of the angles, since the mass was the same.

Once we had the coefficient of friction, we used the formula for weight, which is W = mg, to calculate the weight of the body.The problem was solved by finding the values of the coefficient of friction, which were equal since the mass of the body was the same. The weight of the body was then calculated using the formula W = mg. The main takeaway from this problem is that the coefficient of friction can be used to determine the amount of force needed to move an object, and can also be used to calculate the weight of an object.

This problem can be solved using basic trigonometry and the formula for weight. Therefore, if you encounter a problem similar to this, you can use these concepts to solve it.

We have determined the coefficient of friction to be 0.296, and the weight of the body to be 530 N. This was done by using basic trigonometry and the formula for weight.

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At the starting gun, a runner accelerates at 1.7 m/s2 for 3.7 s. The runner's acceleration is zero for the rest of the race.

a.) What is the speed of the runner at t = 1.3 s?

b.) What is the speed of the runner at the end of the race?

Answers

The speed of the runner at the end of the race is 8.66 m/s and the speed of the runner at t = 1.3 s is 2.21 m/s. the speed of the runner at the end of the race is 8.66 m/s.

The runner accelerates at 1.7 m/s² for 3.7 seconds and the runner's acceleration is zero for the rest of the race.

Here we have to calculate the runner's speed at t = 1.3 seconds and at the end of the race.

So, the acceleration of the runner is 1.7 m/s² and time of acceleration is 3.7 s.

Velocity of the runner after time t is given by the formula:

v = u + atwhere,v is the final velocity

u is the initial velocity

a is the accelerationt is the time taken

The velocity of the runner at t= 1.3 s, we can plug the given values into the above formula:

v = u + atv = 0 + 1.7 x 1.3v = 2.21 m/s

So, the speed of the runner at t = 1.3 seconds is 2.21 m/s.

The speed of the runner at the end of the race, we need to calculate the distance covered by the runner in the first 3.7 seconds during acceleration.

Distance covered by the runner in the first 3.7 seconds is given by the formula:s = ut + (1/2) at²

Where,s is the distanceu is the initial velocity

a is the accelerationt is the time takenInitially, the runner's velocity is zero.

We know the acceleration of the runner, a = 1.7 m/s² and the time taken is t = 3.7 s.

So, Distance covered by the runner in the first 3.7 seconds is,s = 0 + (1/2) x 1.7 x (3.7)²s = 21.98 m

So, the distance covered by the runner in the first 3.7 seconds of the race is 21.98 m.

The runner's velocity at the end of the acceleration is given by the formula:v = √(2as)

Where,v is the final velocitya is the accelerationand, s is the distance

The runner's velocity at the end of the acceleration,v = √(2 x 1.7 x 21.98)v = √(75.156)v = 8.66 m/s

So, the speed of the runner at the end of the race is 8.66 m/s and the speed of the runner at t = 1.3 s is 2.21 m/s. the speed of the runner at the end of the race is 8.66 m/s.

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Suppose a horizontal block-spring system has a spring constant 1,003 N/m and block of mass 3.7 kg. Calculate the frequency in Hz.

Answers

The frequency of the block-spring system is 6.97 Hz.

The frequency (f) of a block-spring system can be calculated using the equation

f = 1 / (2π) * [tex]\sqrt (k / m)[/tex]

where f is the frequency, k is the spring constant, and m is the mass of the block.

Spring constant (k) = 1,003 N/m

Mass of the block (m) = 3.7 kg

Let's calculate the frequency (f):

f = 1 / (2π) *[tex]\sqrt (k / m)[/tex]

= 1 / (2π) *[tex]\sqrt (1,003 / 3.7)[/tex]

≈ 6.97 Hz

The frequency of a block-spring system depends on the spring constant and the mass of the block. In this case, the given spring constant is 1,003 N/m and the mass of the block is 3.7 kg.

By using the formula for frequency, which involves the square root of the ratio of the spring constant to the mass, we find that the frequency is approximately 6.97 Hz.

This means that the block-spring system will complete approximately 6.97 oscillations per second. The frequency represents how fast the system oscillates back and forth, with higher frequencies corresponding to faster oscillations.

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Design an inverting amplifier manually. In PSPICE, please use uA741 and dual power supplies of ±15 V. It must have a closed-loop voltage gain of 32 dB, and input resistance of 2 MΩwhen not loaded. Show your work, and the schematic of your amplifier

Answers

we designed an inverting amplifier with a closed-loop voltage gain of 32 dB using a uA741 Op-Amp. The amplifier has an input resistance of 2 MΩ when not loaded.

The resistor values chosen for Rf, R1, and R2 are 10 kΩ, 9.92 kΩ, and 9.89 kΩ, respectively. This configuration will provide the desired voltage gain and input impedance.To design an inverting amplifier manually, we can follow these steps:

1. Determine the closed-loop voltage gain (Av):
  The closed-loop voltage gain is given as 32 dB. To convert this to a linear scale, we use the formula: Av = 10^(dB/20). In this case, Av = 10^(32/20) = 39.81.

2. Choose a resistor value for Rf:
  We can select a standard resistor value of 10 kΩ for Rf. This value can be adjusted later if needed.

3. Calculate the value of Ri:
  The input resistance, Ri, is given as 2 MΩ when not loaded. To ensure the input resistance remains high, we can use an operational amplifier (Op-Amp) with a high input impedance, such as the uA741.

4. Determine the value of R1:
  Since the amplifier is inverting, the voltage at the non-inverting terminal (pin 3) of the Op-Amp is virtual ground. Therefore, we can assume that the current flowing through R1 is negligible. This allows us to use the equation Ri = R1 || R2, where Ri is the input resistance and R2 is the resistor connected between the inverting terminal (pin 2) and the ground. In this case, R2 is the combination of Rf and R1.

  Rearranging the equation, R1 = Ri * (R2 / (Ri - R2)). Plugging in the values, we get R1 = 2 MΩ * (10 kΩ / (2 MΩ - 10 kΩ)) = 9.92 kΩ.

5. Calculate the value of R2:
  Using the value of R1 calculated in the previous step, we can determine R2 by rearranging the equation R2 = (R1 * Ri) / (Ri + R1). Plugging in the values, we get R2 = (9.92 kΩ * 2 MΩ) / (2 MΩ + 9.92 kΩ) = 9.89 kΩ.

Now that we have the resistor values, we can draw the schematic of the amplifier. However, due to the limitations of this text-based platform, I'm unable to provide a visual representation of the schematic.

To summarize, we designed an inverting amplifier with a closed-loop voltage gain of 32 dB using a uA741 Op-Amp. The amplifier has an input resistance of 2 MΩ when not loaded. The resistor values chosen for Rf, R1, and R2 are 10 kΩ, 9.92 kΩ, and 9.89 kΩ, respectively. This configuration will provide the desired voltage gain and input impedance.

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Doppler ultrasound is used to measure the speed of blood flow. If the speed of the red blood cells is v, the speed of sound in blood is u, the ultrasound source emits waves of frequency f, and we assume that the blood cells are moving directly toward the ultrasound source, then the frequency fr of reflected waves detected by the apparatus is given by Suppose the reflected sound interferes with the emitted sound, producing beats. If the speed of red blood cells is 0.121 m/s, the ultrasound frequency used is 4.95 MHz, and the speed of sound in blood is 1570 m/s, what is the beat frequency?

Answers

The Doppler ultrasound measures the velocity of blood flow. Given that the speed of red blood cells is v, the speed of sound in the blood is u, the ultrasound source emits waves of frequency f, and we assume that the blood cells are moving directly toward the ultrasound source.

Then the frequency fr of reflected waves detected by the apparatus is given by,`fr = f * (u+v) / (u-v)`.When the reflected sound interferes with the emitted sound, it produces beats. We need to find the beat frequency. Given that the speed of red blood cells is 0.121 m/s, the ultrasound frequency used is 4.95 MHz, and the speed of sound in the blood is 1570 m/s.To find the beat frequency, we have to find the difference between the frequency of reflected sound and the emitted sound frequency. The emitted sound frequency f = 4.95 MHz = 4.95 * 10^6 Hz.

The speed of sound in blood is u = 1570 m/s, and the speed of red blood cells is v = 0.121 m/s.So, the frequency of reflected sound is given by,fr = f * (u+v) / (u-v)= 4.95 * 10^6 * (1570+0.121) / (1570-0.121)= 5.54 * 10^6 Hz. Therefore, the beat frequency is given by the difference between the frequency of reflected sound and the emitted sound frequency

| f - fr | = |4.95 * 10^6 - 5.54 * 10^6 |≈ 5.92 * 10^5 HzHence, the beat frequency is approximately 5.92 * 10^5 Hz.

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Consider a series RC circuit for which R = 10.0 MΩ, C = 8.0 µF, and e m f = 35 V. Find the charge on the capacitor 9 s after the switch is closed.

Answers

To find the charge on the capacitor 9 seconds after the switch is closed in a series RC circuit, we can use the formula:

Q = Q0 * (1 - e^(-t / RC))

where:

Q is the charge on the capacitor at time t,

Q0 is the initial charge on the capacitor,

t is the time elapsed since the switch is closed,

R is the resistance in the circuit, and

C is the capacitance of the capacitor.

Given:

R = 10.0 MΩ = 10.0 * 10^6 Ω

C = 8.0 µF = 8.0 * 10^(-6) F

e.m.f. = 35 V

t = 9 s

First, we need to calculate the initial charge on the capacitor (Q0). At t = 0 (when the switch is closed), the capacitor is initially uncharged. Therefore, Q0 = 0.

Now we can substitute the given values into the formula:

Q = 0 * (1 - e^(-9 / (10.0 * 10^6 * 8.0 * 10^(-6))))

Simplifying the equation:

Q = 0 * (1 - e^(-0.00009))

Since e^(-0.00009) is approximately equal to 1 (because the exponential term is very close to zero), the equation becomes:

Q = 0 * (1 - 1) = 0

Therefore, the charge on the capacitor 9 seconds after the switch is closed is 0 C (coulombs).

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A fire hose ejects astream of water at an angle of 30.5

above the horizontal. The water leaves the nozzle with a speed of 27.3 m/5 : Assuming that the water behaves like a projectile, how far from a building should the fire hose be located to hit the highest possible fire? Number Units

Answers

Angle of projection above the horizontal = 30.5°Initial speed of projection of the water stream, u = 27.3 m/sNow, we have to calculate the horizontal distance from the building where the fire hose should be located to hit the highest possible fire.

Let us first consider the vertical component of the initial velocity of the stream of water, which can be given as:  [tex]v_{0_y} = u \sin \theta[/tex] [tex]\implies v_{0_y} = 27.3 \ \text{m/s} \times \sin 30.5°[/tex] [tex]\implies v_{0_y} = 27.3 \ \text{m/s} \times 0.507[/tex] [tex]\implies v_{0_y} = 13.84 \ \text{m/s}[/tex]The time taken to reach the highest point is the same as the time taken to reach the same height during the descent.

Therefore, we can find the time taken to reach the highest point using the vertical component of the initial velocity, which can be given as: [tex]v_y = v_{0_y} - gt[/tex] Where g = 9.81 m/s2 is the acceleration due to gravity. At the highest point, the vertical component of the velocity is zero, i.e. v_y = 0. Therefore, we can solve for t as follows: [tex]0 = 13.84 \ \text{m/s} - 9.81 \ \text{m/s}^2 \times t[/tex] [tex]\implies t = \frac{13.84

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Three point charges are placed at: Q
1

at x=−1,y=0; Q
2

at x=1,y=0;Q
3

at x=0,y=1. What is the magnitude of the total electric field at the origin (x=0,y=0) due to the three charges? Q
1

=127nC,Q
2

=226nC,Q
3

=−92nC⋅l=0.16 m 2) Consider the system of three charges described in the previous problem. The charge Q
1

is moved from the initial position shown in the figure to the origin (x
1

=−l→x
1

=0). What is the resulting change in the electrostatic potential energy of the three-charge system?

Answers

The magnitude of the total electric field at the origin due to the three charges is 2349 N/C. When charge Q1 is moved from its initial position to the origin, the resulting change in the electrostatic potential energy of the three-charge system is -0.145 Joules.

To calculate the magnitude of the total electric field at the origin, we can use the principle of superposition. The electric field at a point due to a single charge is given by Coulomb's law, E = k * Q / [tex]r^2[/tex], where k is the electrostatic constant, Q is the charge, and r is the distance between the charge and the point. Considering all three charges, the electric field at the origin can be calculated by summing the contributions from each charge. For Q1, the distance from the origin is [tex]r1 = \sqrt((-1 - 0)^2 + (0 - 0)^2) = 1[/tex]. Q1's electric field at the origin is E1 = k * Q1 / [tex]r1^2[/tex] = ([tex]9 * 10^9 N m^2/C^2[/tex]) * ([tex]127 * 10^{-9} C[/tex]) / [tex]1^2[/tex] = 1143 N/C.

For Q2, the distance from the origin is [tex]r2 = \sqrt((1 - 0)^2 + (0 - 0)^2) = 1[/tex]. Q2's electric field at the origin is E2 = k * Q2 / [tex]r2^2[/tex] = ([tex]9 * 10^9 N m^2/C^2[/tex]) * ([tex]226 * 10^{-9} C[/tex]) / [tex]1^2[/tex] = 2034 N/C.

For Q3, the distance from the origin is [tex]r3 = \sqrt((0 - 0)^2 + (1 - 0)^2) = 1[/tex]. Q3's electric field at the origin is E3 = k * Q3 / [tex]r3^2[/tex] = ([tex]9 * 10^9 N m^2/C^2[/tex]) * ([tex]-92 * 10^{-9} C[/tex]) / [tex]1^2[/tex] = -828 N/C.

To find the total electric field at the origin, we sum the individual electric fields: [tex]E_{total[/tex] = E1 + E2 + E3 = 1143 N/C + 2034 N/C - 828 N/C = 2349 N/C.

Therefore, the magnitude of the total electric field at the origin due to the three charges is 2349 N/C.

When charge Q1 is moved from its initial position to the origin, the electrostatic potential energy of the system changes. The change in potential energy can be calculated using the formula ΔPE = q * ΔV, where q is the charge being moved and ΔV is the change in potential. Since the charges are fixed and the distance between them remains constant, the change in potential is determined by the change in electric field at the point where the charge is moved. The change in potential energy is equal to the work done in moving the charge against the electric field. In this case, as Q1 is moved from (-1, 0) to the origin (0, 0), the electric field at the origin changes from E1 = 1143 N/C to zero.

Therefore, ΔPE = q * ΔV = Q1 * (0 - E1) = ([tex]127 * 10^{-9} C[/tex]) * (0 - 1143 N/C) = -0.145 Joules.

Hence, the resulting change in the electrostatic potential energy of the three-charge system, when Q1 is moved to the origin, is -0.145 Joules.

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In the circuit, switch S is opened at t=0after having been closed for a long time. At what time is energy stored in the inductor 0.100 times its initial value? Here, A=4.90,B=17.4,C=0.330, and D=11.8. ms

Answers

The time required to have the energy stored in the inductor 0.100 times its initial value is 11.8 ms (rounded to 1 decimal place).

The time at which the energy stored in the inductor is 0.100 times its initial value is calculated by using the formula of the energy stored in the inductor as a function of time which is; E = 1/2 LI².

Here, L is the inductance of the inductor and I is the current flowing through it. So, let's calculate the time required to have the energy stored in the inductor 0.100 times its initial value given that A = 4.90, B = 17.4, C = 0.330, and D = 11.8.Let us write the formula for the energy stored in the inductor as a function of time since switch S is opened.

E = 1/2 LI²Energies stored in the inductor at t=0+ (just after opening the switch) and t=∞ (just before opening the switch) are respectively;`

[tex]E_0 = 1/2 L*I_0^2`[/tex] and `E_∞ = 0` where I0 is the current through the inductor just before opening the switch. Therefore, the energy stored in the inductor can be written as;`

[tex]E(t) = 1/2 L*I(t)^2`[/tex]Let us assume that at some time t, the energy stored in the inductor has reduced to `αE_0` where `α=0.100`So, `E(t) = αE_0` gives [tex]`1/2 L*I(t)^2 = α/2 L*I_0^2`[/tex]

Hence, we have[tex]`I(t)^2 = α*I_0^2[/tex]`And `[tex]I(t) = \sqrt(α)*I_0 = \sqrt(0.1)*I_0`[/tex]

So, `I(t) = 0.316*I_0`The current in an inductor at time t is given by;`I(t) = [tex]I_0*e^(-Rt/L)`[/tex] where R is the resistance in the circuit and L is the inductance of the inductor.

Therefore, we have;`0.316*I_0 =[tex]I_0*e^(-Rt/L)[/tex]`Simplifying the above equation gives;`ln(0.316) = -Rt/L` .Therefore, we have;`t = -L/R*ln(0.316).

`Let's substitute the given values of A, B, C, and D into the above equation to get the time required to have the energy stored in the inductor 0.100 times its initial value.`t = -0.330H/17.4ohms*ln(0.316) = 11.8ms`.

Therefore, the time required to have the energy stored in the inductor 0.100 times its initial value is 11.8 ms (rounded to 1 decimal place).

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A uniform electric field is directed upward and has a magnitude of 1750 N/C. What are the magnitude and direction of the force on a (negative) electric charge of −0.103C placed in this field? A. Force =−16990 N oriented downward. B. Force =+180.25 N oriented downward; C. Force =16990 N oriented upward; D. Force =−180.25 N oriented downward;

Answers

The magnitude and direction of the force on a negative electric charge of -0.103C placed in a uniform electric field with a magnitude of 1750 N/C can be determined using the equation F = qE, where F is the force, q is the charge, and E is the electric field.

To find the magnitude of the force, we substitute the values into the equation:

F = (-0.103C) * (1750 N/C)
F = -180.25 N

The magnitude of the force is 180.25 N.

Since the charge is negative, the force will be directed in the opposite direction of the electric field. Therefore, the direction of the force is downward.

So, the correct answer is D. Force = -180.25 N oriented downward.

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The figure shows two blocks connected by a cord (of negligible mass) that passes over a frictionless pulley (also of negligible mass). The arrangement is known as Atwood's machine. Block 1 has mass m1​=1.2 kg; block 2 has mass m2​=1.8 kg. What are (a) the magnitude of the blocks' acceleration and (b) the tension in the cord? (a) Number Units (b) Number Units

Answers

The magnitude of the blocks' acceleration and the tension in the cord cannot be determined without specific numerical values for g or additional information. The acceleration depends on the difference in mass and the tension in the cord, while the tension depends on the forces acting on each block.

(a) To find the magnitude of the blocks' acceleration, we can use the concept of Newton's second law. The net force acting on the system is equal to the mass of the system multiplied by its acceleration. Considering the tension in the cord as the only force acting on the system, we can write the equation:

Tension = (m2 - m1) * acceleration

Where Tension is the tension in the cord, m2 is the mass of block 2, m1 is the mass of block 1, and acceleration is the magnitude of the blocks' acceleration.

(b) To determine the tension in the cord, we need to consider the forces acting on each block separately. For block 1, the tension pulls it upward, opposing the force due to gravity. For block 2, the tension pulls it downward, aiding the force due to gravity. The tension in the cord is the same for both blocks.

Equating the magnitudes of the forces on each block:

m1 * g - Tension = m1 * acceleration

Tension - m2 * g = m2 * acceleration

Solving these equations simultaneously will allow us to find the value of the tension in the cord.

Without specific numerical values for g or additional information, we cannot provide the exact answers for the magnitude of the blocks' acceleration or the tension in the cord.

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"Determine the force applied to a 11300 g cart, it accelerates
uniformly from rest to a speed of 7.10 m/s over a distance of 35.4
m."

Answers

The force applied to the 11300 g cart is approximately 56.9 N.

Given: Mass of cart, m = 11.3 kg

Initial velocity, u = 0 m/s

Final velocity, v = 7.10 m/s

Distance travelled, s = 35.4 m

Force applied, F =

We can use the kinematic equation v² = u² + 2as, where v is the final velocity, u is the initial velocity, a is the acceleration, and s is the distance travelled.

Rearranging the equation, we get:

a = (v² - u²) / (2s)

Plugging in the given values, we get:

a = (7.10² - 0²) / (2 × 35.4) ≈ 5.03 m/s²

Now, we can use Newton's second law of motion, which states that force (F) is equal to mass (m) multiplied by acceleration

(a).F = ma

Plugging in the values, we get:

F = 11.3 × 5.03 ≈ 56.9 N

Therefore, the force applied to the 11300 g cart is approximately 56.9 N.

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A flea jumps straight up to a maximum height of 0350 in. What is its intia volocity to as a leaves the gound? In the problem, you will apply kinematic equations Express your answer in meters per sucond to throe significant figures. to a jumping flea. Take the magnitude of free-fall acceleration to be 9.80 m/s
2
. Ignore air resibtance. Part B How long is the flea in the air from the time if jumps to the fine it hits the ground? Express your answer in seconds to three signuificant figures.
Previous question

Answers

The initial velocity of the flea as it leaves the ground is approximately 2.61 m/s.

To find the initial velocity of the flea as it leaves the ground, we can use the kinematic equation that relates initial velocity (v0), final velocity (vf), acceleration (a), and displacement (d):

vf² = v0² + 2ad

Since the flea jumps straight up, the final velocity at the highest point is 0 m/s (as it momentarily comes to rest). The acceleration is the acceleration due to gravity, which is approximately 9.80 m/s² (given in the problem). The displacement is the maximum height reached by the flea, which is 0.350 m.

Therefore, the equation becomes:

0 = v0² + 2 * (-9.80 m/s²) * 0.350 m

Simplifying the equation:

v0² = 2 * 9.80 m/s² * 0.350 m

v0² = 6.83 m²/s²

Taking the square root of both sides to solve for v0:

v0 = √(6.83 m²/s²)

v0 ≈ 2.61 m/s

The initial velocity of the flea as it leaves the ground is approximately 2.61 m/s.

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In the problem, you will apply kinematic equations to a jumping flea. Take the magnitude of free-fall acceleration to be 9.80 m/s². Ignore air resistance.

A flea jumps straight up to a maximum height of 0.350 m. What is its initial velocity to as a leaves the ground?

Express your answer in meters per second to throe significant figures.

runner first runs a displacement Aof 3.30 km due south, and then a second displacement B that points due east.

(a)The magnitude of the resultant displacement A + B is 5.42 km. What is the magnitude (in m) of B?

km

What is the angle that A + Bmakes relative to due south? (Your answer must be a positive number from 0 to 180 degrees).

Is this angle east or west of south?

(b)

Consider a situation where the runner still runs a displacement B due east, and we find that the vector A − B has a magnitude of 5.42 km. In this situation, what is the magnitude (in km) of B?

km

What is the angle that A − Bmakes relative to due south? (Your answer must be a positive number from 0 to 180 degrees).

Is this angle east or west of south?

Answers

Runner first runs a displacement A of 3.30 km due south, and then a second displacement B that points due east. Magnitude of B is 4.3 km.  Since vector B points due east, the angle is east of south.

To find the magnitude of vector B, we can use the Pythagorean theorem because the displacement vectors A and B are at right angles to each other. Let's denote the magnitude of vector B as |B|.

Using the Pythagorean theorem, we have:

|A + B| = √(|A|² + |B|²)

Given that |A + B| = 5.42 km and |A| = 3.30 km, we can solve for |B|:

(5.42 km)² = (3.30 km)² + |B|²

29.3764 km² = 10.89 km² + |B|²

|B|² = 29.3764 km² - 10.89 km²

|B|² = 18.4864 km²

|B| = √(18.4864 km²)

|B| ≈ 4.30 km (rounded to two decimal places)

Therefore, the magnitude of vector b is approximately 4.30 km.

To find the angle that A + B makes relative to due south, we can use trigonometry. Let θ be the angle between the resultant vector (A + B) and the due south direction.

tan(θ) = |B| / |A|

tan(θ) = 4.30 km / 3.30 km

θ = atan(4.30 km / 3.30 km)

θ ≈ 52.38 degrees (rounded to two decimal places)

The angle that A + B makes relative to due south is approximately 52.38 degrees. Since vector B points due east, the angle is east of south.

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A bandicoot accelerates from rest until it reaches a tree, 8 m away. How fast is it moving when it reaches the tree? a = 1.5 m/s^2

Answers

The bandicoot is moving at approximately 4.9 m/s when it reaches the tree.

To find the speed at which the bandicoot reaches the tree, we can use the kinematic equation:

[tex]v^2 = u^2 + 2as[/tex]

Where v is the final velocity, u is the initial velocity (which is 0 in this case since it starts from rest), a is the acceleration, and s is the distance.

Given:

u = 0 m/s (starting from rest)

a = 1.5 m/s^2

s = 8 m

Plugging these values into the equation, we have:

[tex]v^2 = 0^2 + 2 * 1.5 * 8[/tex]

[tex]v^2 = 0 + 24[/tex]

[tex]v^2 = 24[/tex]

Taking the square root of both sides, we find:

v = √24

v ≈ 4.9 m/s.

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A shield that contains 10 identical holes in a linear array is required to have 20 dB of shielding effectiveness at 300MHz. What is the maximum linear dimension of one hole?

Answers

A shield that contains 10 identical holes in a linear array is required to have 20 dB of shielding effectiveness at 300MHz. The maximum linear dimension of one hole in the shield is 10 meters.

The maximum linear dimension of one hole in the shield can be determined using the concept of shielding effectiveness and the given requirements.
Shielding effectiveness (SE) is a measure of how well a shield can block electromagnetic radiation. It is usually expressed in decibels (dB).
In this case, the shield needs to have a shielding effectiveness of 20 dB at a frequency of 300 MHz.
To calculate the maximum linear dimension of one hole, we can use the equation:
SE = 20log10(d/λ)
where SE is the shielding effectiveness, d is the maximum linear dimension of one hole, and λ is the wavelength of the radiation.
To solve for d, we can rearrange the equation as follows:
d = λ * 10^(SE/20)
First, we need to find the wavelength of the radiation at a frequency of 300 MHz. The formula to calculate wavelength is:
λ = c/f
where λ is the wavelength, c is the speed of light (approximately 3 x 10^8 meters per second), and f is the frequency in hertz.
Substituting the values, we have:
λ = (3 x 10^8) / (300 x 10^6)
λ = 1 meter
Now, we can calculate the maximum linear dimension of one hole using the formula:
d = 1 meter * 10^(20/20)
d = 1 meter * 10^1
d = 10 meters
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What is the normal force exerted by an object at rest placed on a horizontal plane equal to?

Answers

Answer:

The plane supports the object - the only force acting on the object is

W = weight

Fn (normal force exerted by plane) = W

Fn = W = M g

A 6.4-kg mass slides down a flat hill that makes an angle of 54\deg with the horizontal. If friction is negligible, what is the resultant force on the sled?

Answers

The resultant force on the sled is equal to the component of the gravitational force acting along the direction of the hill, which is the force due to gravity multiplied by the sine of the angle of the hill.

When a mass slides down a hill, the force of gravity can be resolved into two components: one perpendicular to the hill (normal force) and one parallel to the hill (resultant force). Since friction is negligible, the only force acting along the hill is the component of the gravitational force.

To find the resultant force on the sled, we multiply the force due to gravity (weight) by the sine of the angle of the hill. The weight of the sled can be calculated using the formula weight = mass * gravitational acceleration. In this case, the mass is given as 6.4 kg.

Once we have the weight, we can find the resultant force by multiplying it by the sine of the angle of the hill, which is 54 degrees. The sine function relates the length of the side opposite to an angle in a right triangle to the length of the hypotenuse. Thus, the resultant force on the sled is determined.

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"You and your team are performing an experiment involving
tension, 3 frictionless blocks, and 2 ideal pulleys, configured as
displayed in the figure below. Each mass is as follows: mA = 2 kg,
mB = 7 kg"

Answers

In the experiment involving tension, three frictionless blocks, and two ideal pulleys that are configured as shown in the figure below, there are two masses involved:

mA = 2 kg and mB = 7 kg.

Here's how the experiment works:

a string that has negligible mass is wrapped around the two pulleys, which are ideal and have no friction. The blocks are connected by the string, and they can slide freely without any friction on the surface that they are resting on. Initially, the blocks are at resT,

The force will be applied to one of the blocks, and it will cause the blocks to move in the direction of the force. The tension in the string is denoted by T. It is equal to the force that is applied to the blocks.

There are two masses involved in the experiment.

They are labeled as mA and mB.

The acceleration of the blocks is denoted by a. When a force is applied to one of the blocks, it will cause both blocks to move in the direction of the force.

The acceleration of the blocks can be calculated using the following equation:

a = T / (mA + mB) The tension in the string can be calculated using the following equation:

T = mA * a + mB * a

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A 1200 kg sports car accelerates from 0 m/s to 26 m/s in 11 s. What is the average power of the engine in kW?

Answers

The average power of the engine is approximately 37.07273 kW.

To calculate the average power of the engine, we can use the equation: Power = (Change in kinetic energy) / (Time)

First, let's calculate the change in kinetic energy of the car. The initial velocity is 0 m/s, and the final velocity is 26 m/s.

Therefore, the change in velocity is:

Change in velocity = Final velocity - Initial velocity

                               = 26 m/s - 0 m/s

                               = 26 m/s

The mass of the car is given as 1200 kg.

Using this information, we can calculate the change in kinetic energy: Change in kinetic energy = (1/2) * mass * (Change in velocity)²

                                          = (1/2) * 1200 kg * (26 m/s)²

                                          = 1/2 * 1200 kg * 676 m²/s²

                                          = 1/2 * 1200 kg * 676 kg * m²/s²

                                          = 406800 kg * m²/s²

Now, let's calculate the time taken for the car to accelerate. The time given is 11 s.

Next, we can substitute the values into the power equation:

Power = (Change in kinetic energy) / (Time)

          = 406800 kg * m²/s² / 11 s

          = 37072.73 kg * m²/s³

Finally, let's convert the power from watts to kilowatts:

1 kW = 1000 W

Power in kilowatts = 37072.73 W / 1000

                               = 37.07273 kW

Therefore, the engine's typical output is about 37.07273 kW.

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Four-point starter is used when a) Motor field current is varied in narrow range b) Motor speed is varied in small range c) Motor field current is varied over wide range d) Can be used anywhere

Answers

The correct answer is c) Motor field current is varied over a wide range.A four-point starter is a type of starter used in electrical motors to control the field current. It is specifically designed to vary the motor's field current over a wide range.

Here's how a four-point starter works:

1. The starter consists of four main points: two main contacts (known as the line contacts) and two auxiliary contacts (known as the shunt contacts).

2. When the motor is initially started, the main contacts are closed, allowing current to flow through the motor's field windings.

3. As the motor starts to gain speed, the shunt contacts start to open gradually. This reduces the amount of current flowing through the field windings.

4. By controlling the amount of current in the field windings, the motor's magnetic field strength can be adjusted. This, in turn, affects the motor's speed.

5. The wide range of variation in the motor's field current allows for precise control over the motor's speed, making the four-point starter suitable for applications where speed control is crucial.

To summarize, a four-point starter is used when the motor's field current needs to be varied over a wide range. This allows for precise speed control of the motor.

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State whether the following statement is true or false, and explain why. If the statement is false, state the true change. If the price of avocados increases by 25% for four consecutive months, then the price of avocados increased by 100% over the four-month period. Choose the correct answer below and fill in the answer box to complete your choice. The statement is false because each year there is a different reference value. The statement is true because 425%=100%. What percentage did the avocados increase by? % (round to a tenth of a percent) the uneroveyment rate has naw Discuss three actions, from a security perspective, that are important in theemployee-termination process. Three parallel three-phase loads are supplied from a 207.85-Vrms, 60-Hz three-phase supply. The loads are as follows: Load 1: 8kW with 0.6 lagging power factor. Load 2: Resistive load of 8kW. Load 3: capacitor load of 19 kvar. (a) What is the total system kW, kvar, power factor, and the supply current per phase? (b) What is the system power factor and the supply current per phase when the Load-1 and Load-2 are operating but the Load-3 is switched off? Read the following case study and answer the questions:FINANCIAL PROJECTIONS OF EMPIRE LIMITEDEmpire Limited was established in Gauteng in 2017, manufacturing medical equipment and supplies with an initial capital of 5 000 000 ordinary shares that were issued at R1 each. The sales of the company, which are all on credit, grew steadily during 2018 and 2019 but increased rapidly during 2020 and 2021 following the business opportunities presented to the company by Covid-19. The sales for 2021 increased to R9 000 000 and the directors predicted that the sales for 2022 would increase by 20%. At the end of 2021 the accumulated undistributed profits amounted to R1 600 000, fixed assets (at carrying value) totalled R6 000 000, R900 000 was owed to trade creditors, inventories amounted to R5 500 000 and an amount of R4 000 000 was owed to Jap Bank in respect of a long-term loan.The directors were interested to know what the financial position of the company would look like at the end of 2022 based on the following additional predictions and information for 2022:A gross margin of 45% and net profit margin of 20% were forecast. The cost of production of finished goods for the year is estimated at R6 500 000. The company provides its customers credit terms of 60 days but a collection period of 73 days is predicted. The percentage-of-sales method is used to estimate the accounts payable. A favourable bank balance of R300 000 is expected on 31 December 2022.Vehicles with a cost price of R500 000 and accumulated depreciation of R400 000 are expected to be sold at the end of 2022 at a profit of R50 000. Due to the expected growth in sales, delivery vehicles with a cost price of R5 000 000 will be purchased. The total depreciation for 2022 is estimated at R1 200 000.Dividends of R1 500 000 are expected to be recommended by the directors at the end of December 2022. These dividends will be paid to the shareholders during 2023. R1 200 000 will be paid to Jap Bank during 2022. This amount includes R500 000 for interest. The amount of external funding (non-current debt) required to fund the growth in the company must be determined (balancing figure).The directors are also considering investment opportunities for 2023 and have identified, amongst others, the purchase of additional machinery to increase the productive capacity. The expected cost of the machinery is R8 000 000 with a useful life of five years and no scrap value. Depreciation is calculated on a straight-line basis. The new machinery is expected to increase net profit by R950 000 per year. The company's cost of capital is 15%. The number of visitors to a certainWeb site triples every month. Thenumber of visitors is modeled by theexpression 8100.3m, where m is thenumber of months after the numberof visitors was measured. Evaluatethe expression for m =-4. Answer as if it relates to answering questions for a job interview and youre applying for an HR Managerial position. 3. What are your greatest strengths? 4. What are your weaknesses? polytropic process is a thermodynamic process that obcys the relation: pV = constant The exponent is known as the polytropic index, and it may take on any value from 0 to [infinity] depending on the particular process: =0,p= constant, corresponds to an isobaric (constant-pressure) process; [infinity] corresponds an isochoric (constant-volume) process; =1,pV= constant, corresponds to an isothermal (constant-temperature) procas; =,pV= constant, corresponds to an iscntropic (constant-cntropy) process. Prove that in a polytropic expansion of an ideal gas defined by the equation pV = constant the gas absorbs heat for , where =c p /c V . A student bikes to school by traveling first d N = 0.900 miles north, then d W =0.400 miles west. and finally d S =0.100 miles south. Similarly, let d W be the displacement vector corresponding to the second leg of the student's trip. Express d W in component form. Express your answer as two numbers separated by a comma. Be careful with your signs. he vector A =(A x ,A y )=(+7.07m,+7.07 m) and the vector B =(B x ,B y )=(+5.00m,+8.66 m). What is the magnitude of the angle between the vectors A ^ and B ? 15 30 45 60 75 Five males with an X-linked genetic disorder have one child each. The random variable x is the number of children among the five who inherit the X-linked genetic disorder. Determine whether a probability distribution is given. If a probablity distribution is given, find its mean and standard deviation. If a probability distribution is not given, identify the requirements that are not satisfied. A. Yes, the table shows a probinblity distribution 8. No, the random vartable x is categotical instead of numerical C. No the random variable x n number values are not assoclated with probabilites 6. No: the sam of ail the probabilities is not equal to 1 E Na not every prokabllity is between 0 and t incluslve A currency trader sees the following information on his computer screen:Spot Rate: NKr6.2280/$3-month forward rate: NKr6.2640/$US 3-month Treasury Bill rate: 1.4%Norwegian 3-month Treasury Bill rate: 1.8%The currency trader can borrow up to Nkr6.228m (or the equivalent of $1m).(i) As implied by market prices, state how the value of the $ is expected to change over the next three months. (5 marks)(ii) Calculate the annualised forward premium/discount at which the NKr is trading against the $. (5 marks)(iii) Explain why theory suggests that Interest Rate Parity (IRP) should hold between countries and demonstrate (with calculations) whether or not IRP is currently holding between Norway and the US. (15 marks)(iv) Demonstrate (with calculations) how a covered interest arbitrage profit can be achieved in this situation, stating clearly the amount of the profit that can be achieved. (15 marks)(v) Explain precisely how IRP will be restored as a result of such covered interest arbitrage activities, stating clearly the impact on interest rates in the two countries and the spot and forward exchange rates between the two currencies. (10 marks) A project requires a cash outflow of -$1000 today. Incoming cash flows are forecast to be $500 after one year, $500 after two years, and $500 after three years.What is the payback period in years?Enter a 0 if not enough information is given to calculate the answer.Formatting instructions:#####0whole numbers onlyno decimalsno dollar signno commasexample: 12345678 What are the strength and direction of the electric field at the position indicated by the dot in the figure(Figure 1)? Give your answer in component form. (Assume that x-axis is horisontal and points to the right, and y-axis points upward.) Express your answer in terms of the unit vectors i ^ and j ^ . Express your answer using two significant figures. Part B Give your answer as a magnitude and angle measured cw from the positive x-axis. Express your answer using two significant figures. Figure Part C Express your answer using two significant figures. A soccer ball is kicked from the ground with an initial velocity of 17.9 m/s, at an angle of 20.5 degrees with respect to the horizontal. Once the ball reaches its maximum height, what is the velocity in the x direction at that moment? Ignore air resistance You have a hot water tank in the unheated basement. It is wrapped in 1.5 inches of urethane foam (R-value = 6.6). The tank has a surface area of 4.5 m^2. What is the rate of energy loss if the water inside the tank is 125 F and the basement ambient air is 55 F?. Compare this estimate to one in which you wrap an additional 3.5"" of fiberglass insulation around the water heater. How much less rate of energy loss is there with the additional insulation A projectile is launched at ground level with an initial speed of 58 m/s at an angle of 34 above the horizontal. It strikes a target above the ground 4 seconds later. What are the x and y distances from where the projectile was launched to where it lands? 2. The market for capitalFirms require capital to invest in productive opportunities. The best firms with the most profitable opportunities can attract capital away from inefficient firms with less profitable opportunities. Investors supply firms with capital at a cost called the interest rate. The interest rate that investors require is determined by several factors, including the availability of production opportunities, the time preference for current consumption, risk, and inflation.Suppose the Federal Reserve (the Fed) decides to tighten credit by contracting the money supply. Use the following graph by moving the black X to show what happens to the equilibrium level of borrowing and the new equilibrium interest rate. Stock A has and initial price of $93, an ending price of $102, and 1,000 shares of common stock outstanding. Stock B has an initial price of $35, an ending price of $32, and 8,000 shares of common stock outstanding. Calculate the price-weighted return over the time period A 200.kg motor is hanging on a cable, what is the tension in the cable in Newtons? It now descends at 1.1 m/s 2 . What is the tension in the cable now? 3. Earl sells lemonade in a competitive market on a busy street corner in Davenport. His production function is F(K.L) = (1/3) [(1/3), where output is measure in gallons, K is the number of pounds of lemons he uses, and L is the number of labor hours spent squeezing them. (a) Let wk is the cost of a pound of lemons and w is the wage rate for lemon-squeezers. If Earl is going to produce y units in the cheapest way possible, find the number of pounds of lemons he uses and the number of hours of labor that he will use.