if you rub a ballon with wool or duster it can charge it negatively where do these extre charge come from?​

Answer:

[tex] \sf \: given \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \\ \bf \: mass \: \: \: m \: = 7.00 \times {10}^{ - 4} \: kg \\ \\ \bf \: E=mc^2 \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \: \\ \\ = > E=7.00 \times {10}^{ - 4} \times ({3 \times {10}^{8} })^{2} \\ \\ = > \green{ \boxed{ E = 6.3 \times {10}^{13} \: J}}[/tex]

Explanation:

light travel slower in daimond

Answer:

θ = 66º

Explanation:

This exercise of Newton's second law must be solved in part, let's start by finding the slowing down acceleration of the ball

           a = v² / r

the radius of the circle is

          sin θ = r / L

          r = L sin θ

we substitute

          a = v² /L sin θ

now let's write Newton's second law

vertical axis

            T_y -W = 0

             T_y = W

radial axis

            Tₓ = m a                 (1)

let's use trigonometry for the components of the string tension

             cos θ = T_y / T

             sin θ = Tₓ / T

             Tₓ = T sin θ

we substitute in 1

            T sin θ = [tex]\frac{m \ v^2}{L \ sin \theta}[/tex]

             T L sin² θ = m v²

we write our system of equations

             T cos θ  = m g

             T L sin ² tea = m v²

we divide the two equations

             L [tex]\frac{sin^2 \theta}{cos \theta}[/tex] = v² / g

             (1 -cos²)/ cos θ  = [tex]\frac{v^2 }{g \ L}[/tex]

             1 - cos² θ  =  [tex]\frac{4.75^2}{9.81 \ 2.37}[/tex]   cos θ

             cos² θ + 0.97044 cos θ -1   = 0

we change variable    cos  θ = x

             x² + 0.97044 x - 1 =0

             x= [tex]\frac{-0.97 \pm \sqrt{0.97^2 - 4 1} }{2}[/tex]

           since the square root is imaginary there is no real solution to the problem, suppose that the radius is 1 m r = 1 m

           T sin θ = [tex]\frac{m \ v^2}{ r}[/tex]

           T cos θ  = m g

resolved

           tan θ =  [tex]\frac{v^2}{ r g}[/tex]

           θ = tan⁻¹ ( 4.75²/ 1 9.81)

           θ = 66º

Answer:

I_syst = 278.41477 kg.m²

Explanation:

Mass of platform; m1 = 117 kg

Radius; r = 1.61 m

Moment of inertia here is;

I1 = m1•r²/2

I1 = 117 × 1.61²/2

I1 = 151.63785 kg.m²

Mass of person; m2 = 62.5 kg

Distance of person from centre; r = 1.05 m

Moment of inertia here is;

I2 = m2•r²

I2 = 62.5 × 1.05²

I2 = 68.90625 kg.m²

Mass of dog; m3 = 28.3 kg

Distance of Dog from centre; r = 1.43 m

I3 = 28.3 × 1.43²

I3 = 57.87067 kg.m²

Thus,moment of inertia of the system;

I_syst = I1 + I2 + I3

I_syst = 151.63785 + 68.90625 + 57.87067

I_syst = 278.41477 kg.m²

Answer:

H + H ------> He + energy. He + He -----> H + H + He.

Explanation:

Hydrogen having one proton and no neutron fuse with hydrogen having one proton and one neutron forming helium atom with the release of photon. After that two helium atoms combine together forming two hydrogen atoms having one proton each whereas one helium atom having two protons and two neutrons present in their nucleus so the end product of this reaction is hydrogen atoms and helium.

Explanation:

..upper side is glass ..

Answer:

v = 50.5 m/s

Explanation:

F = (m)(^v/^t)

115N = (0.04551kg)(v/(0.020s))

2,526.917161 m/s² = v/(0.020s)

v = 50.53834322 m/s

v = 50.5 m/s

Answer:

force and surface area are two factors affecting pressure on solids

more the force you apply, more will be the pressure

pressure and force are directly proportional meaning if Force is greater, pressure will also be greater

more the surface area of the solid less will be the pressure

surface area and pressure are inversely proportional meaning if surface are is big, pressure will be less, surface area small, pressure will be greater

Answer and Explanation:

We have a basic equation: Pressure = Force/Area.

So for example:

Increase pressure - increase the force or reduce the area the force acts on.

Decrease pressure - decrease the force, or increase the area the force acts on

The force per unit area is pressure. The force on the object is spread over the surface area. The area where the force is applied is divided by the equation for pressure.

Cheers,

Answer:

The centripetal acceleration of the stone is 5 m/s²

Explanation:

The length of the string to which the stone is attached, r = 1 m

The speed with which the string is rotated, v = 5 m/s

The centripetal acceleration, [tex]a_c[/tex], is given as follows;

[tex]a_c = \dfrac{v^2}{r}[/tex]

Therefore, the centripetal acceleration of the stone found as follows;

[tex]a_c = \dfrac{(5 \ m/s)^2}{1 \ m} = 5 \ m/s^2[/tex]

The centripetal acceleration of the stone, [tex]a_c[/tex] = 5 m/s².

Answer:

He is suffering from hypermetropia.

Explanation:

There are some defects of vision.

Longsightedness of hypermetropia : It is the defect of vision in which the person is not able to see the nearby objects clearly but can see the far off objects clearly. This is due to the elongation of size of eye ball. It is cured by using convex lens of suitable focal length.

Nearsightedness or Myopia : It is the defect of vision in which a person is not able to see the far off objects clearly but can see the nearby objects clearly. It is due to the contraction in the size of eye ball. It is cured by using concave lens of suitable focal length.

So, Hideki is suffering from hypermetropia. So, he should use the convex lens of suitable focal length.  

Answer:

Distance cover in 2  hour = 6 kilometer

Explanation:

Given equation:

x = 2t - 10

where

x = kilometer

t = hour

Find:

Distance cover in 2  hour

Computation:

T = 2

So,

x = 2t - 10

x = 2(2) - 10

x = 4 - 10

x = -6

Distance cover in 2  hour = 6 kilometer

Answer:

The distance is 6 km.

Explanation:

The equation of uniform linear motion of a particle has the form: x = 2t – 10. (x: km, t: h). What is the distance traveled by the particle after 2 hours?

x = 2t - 10

distance traveled after t = 2 hours

Substitute t = 2 in the given expression

x = 2 x 2 - 10

x = 4 - 10

x = - 6 km

So, the distance is 6 km.

Answer:

10N is the answerrrerreer

Answer:

f= 100N

Explanation: F=m×(v₀-vf/t)

=0.05ₓ(200-0/0.1)

=0.05ₓ2000

=100N

please mark as brainliest

Answer:   Let us calculate the pressure exerted on the bottom by the weight of the fluid. That pressure is the weight of the fluid mg divided by the area A supporting it (the area of the bottom of the container): P=mgA P = m g A .

Explanation:

Answer:

enertia

Explanation:

enertia

The correct answer is (B) Centrifugal Force

The centrifugal force on a vehicle on the curves is outwards or can say away from the curve and pulls the out of the track.

the centrifugal force is given by [tex]F=\frac{mv^{2} }{r}[/tex], which is directly proportional to speed v.

Speed limits on the curves help in reducing the centrifugal force by reducing the speed.

Learn more about centrifugal force:

https://brainly.com/question/25546106

Explanation:

The acceleration g varies by about 1/2 of 1 percent with position on Earth's surface, from about 9.78 metres per second per second at the Equator to approximately 9.83 metres per second per second at the poles.

Answer:  An effect of continental drift is causing tectonic plates resting upon the convecting mantle to move which results in natural disasters like earthquakes, volcanic eruptions, and more.

Complete Question:

A long distance runner running a 5.0km track is pacing himself by running 4.5km at 9.0km/hr and the rest at 12.5km/hr. What is the average speed?​

Answer:

Average speed = 9.7333 km/h

Explanation:

Given the following data;

To find the average speed;

First of all, we would determine the time taken to cover distance A in speed A by using the formula;

[tex] Time \ A = \frac {Distance \; A}{Speed \; A} [/tex]

Substituting the values into the formula, we have;

[tex] Time \ A = \frac {4.5}{9.5} [/tex]

Time A = 0.4737 hours

Total distance = distance A + distance B

5 = 4.5 + distance B

Distance B = 5 - 4.5

Distance B = 0.5 Km

Next, we would determine the time to cover distance B in speed B;

[tex] Time \ B = \frac {0.5}{12.5} [/tex]

Time A = 0.04 hours

Total time = time A + time B

Total time = 0.4737 + 0.04

Total time = 0.5137 hours

Now, we would solve for the average speed;

Mathematically, the average speed of an object is given by the formula;

[tex] Average \; speed = \frac {total \; distance}{total \; time} [/tex]

[tex] Average \; speed = \frac {5}{0.5137} [/tex]

Average speed = 9.7333 km/h

Explanation:

(b) A uniform beam 150cm long weighs 3.5kg and

supported on knife-edges at its ends. The beam

supports a weight 7kg at a distance 30cm from

one end. Find the reactions of the supports.

Answer:

divide the density of solution by density of water

EXPLANATION:

LIKE:

1.25÷1000kgm-3

perpose of lab is to store apparatus and do some experiment

Helps someone to know the exert lengh of something

The temperature of a gas molecule is measured by the average translational kinetic energy

Answer:

The temperature of a gas is a measure of the average translational kinetic energy of the molecules. In a hot gas, the molecules move faster than in a cold gas; the mass remains the same, but the kinetic energy, and hence the temperature, is greater because of the increased velocity of the molecules

Explanation:

This is also from Go0gle because my explanation would've been an essay long .

but in shorter version if the gas molecules move fast it's hot an if it moves slow its cold hope this helps .

Answer:

Explanation:

To find the horizontal component, the x component specifically, use the formula:

[tex]V_x=Fcos\theta[/tex] and for the vertical component, the y component, use the formula:

[tex]V_y=Fsin\theta[/tex]

where F is the magnitude of the force and theta is the angle in degrees.

For the x-component:

[tex]V_x=6cos250[/tex] so

[tex]V_x=-2.1[/tex] and depending upon whether this is a displacement vector or a velocity vector, the label would be meters/feet or m/s, respectively.

For the y-component:

[tex]V_y=6sin250[/tex] so

[tex]V_y=-5.6[/tex]

Answer:

The answer is "[tex]1.2566 \times 10^{-5}\,rad[/tex]".

Explanation:

As per the Rayleigh Criterion the minimum angular spreading, for a circular aperture:

[tex]\theta_{\mathrm{min}}\approx \sin\theta=1.22\,\frac{\lambda}{d}[/tex]  

[tex]\theta_{\mathrm{min}}=\mathrm{1.22\,\frac{\left( 610\,nm \right)}{\left( 5.90\,cm \right)}=1.22\,\frac{\left( 610\times10^{-9}\,m \right)}{\left( 5.90\times10^{-2}\,m \right)}}[/tex]

                               [tex]=1.22\times 103.389 \times 10^{-7}\\\\=1.22\times 1.03 \times 10^{-5}\\\\=\mathrm{1.2566 \times 10^{-5}\,rad}[/tex]

Answer:

A dicot is a flowering plant that has one seed leaves. The monocot plants have a single cotyledon. Maize only has one cotyledon in their seed, so it's a monocot. Seeds having two Cotyles are mainly called a Dicot. A pea is a dicotyledonous plant, the seed (the pea itself) has two halves, cotyledons, hence dicot being 2.

Explanation:

One or more of the cotyledons are the first to appear from a germinating seed. Based on the number of cotyledons, botanists classify flowering plants (angiosperms) into :

a) plants with one embryonic leaf, termed monocotyledonous (monocots).

b) plants with two embryonic leaves, termed dicotyledonous (dicots).

Helpful Link:

https://www.vedantu.com/question-answer/in-pea-caster-and-maize-the-number-of-cotyledons-class-11-biology-cbse-5f626a17e5bde9062ff6d2a3

Answer:

Explanation:

Discount the time here; it's not important. It doesn't tell you how long it takes the car to stop, it only refers to reaction time, which means nothing in the scheme of things.

The useful info is as follows:

initial velocity = 20 m/s

final velocity = 0 m/s

a = -10 m/s/s

and we are looking for the displacement. Use the following equation:

[tex]v^2=v_0^2+2a[/tex]Δx

where v is the final velocity, v₀ is the initial velocity, a is the deceleration (since it's negative), and Δx is displacement. Filling in:

[tex]0^2=(20)^2+2(-10)[/tex]Δx and

0 = 400 - 20Δx and

-400 = -20Δx so

Δ = 20 meters

Vtb xe máy là:

v=s : t= 500 : 25=20(m/s)

Total distance = 10 km + 10 km = 20 km

1 km = 1000 m

20km x 1000 = 20,000 m

Total time = 20 min. + 30 min. = 50 minutes

Average speed = Distance /  time

Average speed = 20,000/50 min

Average speed = 400 m/s