(A) A triangular glass prism of thickness 12cm is placed on a mark on a piece of paper resting on a horizontal bench. If the refractive index of the material of the prism is 1.5, calculate the apparent displacement of the mark.

(B)Water is poured into a jar to a depth of 24cm. The bottom of the jar appears
to be raised by 6cm when viewed vertically. Calculate the refractive index of water.

Answers

Answer 1

Part A - The apparent displacement of the mark is 4 cm.

The refractive index of a material, n = real depth, D/apparent depth, L.

So, n = D/L

Since the refractive index of the triangular glass prism is 1.5, n = 1.5. Also, the triangular glass prism is 12 cm thick and placed on a mark on a piece of paper resting on a horizontal bench. So, the real depth of the mark on the piece of paper through the triangular prism is D = 12 cm and its apparent depth is L.

Since n = D/L,

making L, subject of the formula, we have

L = D/n

Substituting the values of the variables into the equation, we have

L = D/n

L = 12 cm/1.5

L = 8 cm

so, the apparent depth of the mark is 8 cm.

So, the apparent displacement of the mark is d = D - L = 12 cm - 8 cm = 4 cm

Thus the apparent displacement of the mark is 4 cm.

Part B - The refractive index of water, n = 1.33.

The refractive index of a material, n = real depth, D/apparent depth, L.

So, n = D/L

Since the depth of water in the jar is 24 cm, the real depth, D = 24 cm.

Also, the bottom of the jar appears to be raised by 6 cm. So, the apparent depth, L = 24 cm - 6 cm = 18 cm

Since n = D/L, the refractive index of water n = D/L

Substituting the values of the variables into the equation, we have

n = D/L

= 24 cm/18 cm

= 1.33

So, the refractive index of water, n = 1.33.

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Related Questions

The heat required to raise 3 kg of copper from 0°C to 10°C raises 1kg of lead from 10°C to 100°C. If the specific heat capacity of copper is 0.095 cal/g°C,find the specific heat capacity of lead.​

Answers

The specific heat capacity of lead has been determined to be 0.032 cal/g°C.

The specific heat capacity of a substance is the amount of heat required to increase the temperature of its unit mass by 1 Kelvin rise in temperature.  There is no phase change during the process. This can be expressed as:

Q = mcT

c = [tex]\frac{Q}{mT}[/tex]

Where c is the specific heat capacity of the substance, Q is the quantity of heat required, m is the mass of the substance and T is its change in temperature.

In the given question, the heat emitted by the copper mass would be absorbed by the lead mass.

So that;

heat emitted by copper = heat absorbed by lead

[tex]m_{c}[/tex] [tex]c_{c}[/tex]([tex]T_{2}[/tex] - [tex]T_{1}[/tex]) = [tex]m_{l}[/tex][tex]c_{l}[/tex]([tex]T_{2}[/tex] - [tex]T_{1}[/tex])

With the given information in the question, the above equation is expressed as:

3 * 0.095 * (10 - 0) = 1 * [tex]c_{l}[/tex]* (100 - 10)

3*0.095*10 = [tex]c_{l}[/tex] * 90

2.85 = [tex]c_{l}[/tex]*90

[tex]c_{l}[/tex] = [tex]\frac{2.85}{90}[/tex]

  = 0.031667

[tex]c_{l}[/tex] = 0.032 cal/g°C

Therefore, the specific heat capacity of lead is 0.032 cal/g°C.

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The speed of sound where a tuning fork of frequency 262 Hz produces the third resonance position above a closed air column that is 1.59 m in length is ___m/s.

Answers

Answer:

v = 333.26 m/s

Explanation:

Given that,

The frequency of the tuning fork, f = 262 Hz

It produces the third resonance position above a closed air column that is 1.59 m in length.

We need to find the speed of sound in tuning fork. Let it is f. The third resonance position corresponds to the fifth harmonic of the closed air column. The wavelength in third resonance is given by :

[tex]\lambda=\dfrac{4}{5}L\\\\=\dfrac{4}{5}\times 1.59\\\\=1.272\ m[/tex]

The speed of sound is :

[tex]v=f\lambda\\\\=262\times 1.272\\\\=333.26\ m/s[/tex]

So, the speed of sound is 333.26 m/s.

Answer:

The speed of sound is 555.44 m/s.

Explanation:

frequency of third resonance position, f''' = 262 Hz

length of pipe, L = 1.59 m (closed)

Let the speed is v.

The frequency of third resonance in closed organ pipe is

[tex]f''' =\frac{3 v}{4 L}\\\\262 = \frac{3 v}{4\times 1.59}\\\\v = 555.44 m/s[/tex]

Two charges 3*10^-5 C and 5*10^4 C are placed at a distance 10 cm form each other. Find the value of electrostatic force acting between them. a) 13.5 x 10^11N b) 40 x 10^11N c)180 x 10^9N d)13.5 x 10^10 N

Answers

Answer:

13.5 x 10^(11) N

Explanation:

Given :

The magnitude of charge 1 = q1 = 3 × 10^(-5) C

The magnitude of charge 2 = q2 = 5 × 10^(4) C

The distance between charges = d = 10 cm = 0.1 m

To Find :

The magnitude of electrostatic force acting between charges

Solution :

∵ Electrostatic force = F = (k × (q1) x (q2)) / r^(2)

where k = 9 × 10^(9)

i.e    F = 9 × 10^(9) × (3 × 10^(-5) × 5 × 10^(4)) / (0.1)^(2)  

Or, F =  9 × 10^(9) ×  (1.5/0.01)  

∴   F = 9 × 10^(9) × 150

i.e F = 1350 × 10^(9)

or,  Force = F = 1.35 × 10^(12) N

Hence, The magnitude of electrostatic force acting between charges is  1.35 × 10^(12) N => 13.5 x 10^(11)

Two rams run toward each other. One ram has a mass of 44 kg and runs south with a speed of 6 m/s, while the other has a mass of 50 kg and runs north with a speed of 3 m/s. What will the momentum of the system made up of the two rams be after they collide? Assume the total momentum of the system is conserved.
A. 114 kg-m/s south
B. 414 kg-m/s south
C. 414 kg m/s north
D. 114 kg-m/s north

Answers

Answer = D. 114 kg-m/s north

is there any machine that is 100% efficient? why?why not

Answers

Answer:

No, it's not there.

Explanation:

For a machine to be 100% efficient, it has to be with an output which is equal to its input. But machines have an out put less than an input, hence efficiency below 100%.

A body starts with an initial velocity of 15m/s and accelerates 4m/s2. Find the distance covered by 5s

Answers

Answer:

Distance, S = 110 meters

Explanation:

Given the following data;

Initial velocity = 15 m/s

Acceleration = 4 m/s²

Time = 5 seconds

To find the distance covered, we would use the second equation of motion;

[tex] S = ut + \frac{1}{2} at^{2} [/tex]

Where;

S is the distance covered or displacement of an object.

u is the initial velocity.

a is the acceleration.

t is the time.

Substituting the values into the equation, we have;

[tex] S = 15*4 + \frac{1}{2} * 4*5^{2} [/tex]

[tex] S = 60 + 2*25 [/tex]

[tex] S = 60 + 50 [/tex]

Distance, S = 110 meters


Describe in brief
brief the scope and excitement
in Physics

Answers

Answer:

The scope of physics is quite vast and covers an enormous range of magnitude of physical quantities like mass, length, time, energy etc.

The scope is divided into two sections, where on one side it studies about phenomena at a very small microscopic level involving and analyzing electrons, protons, and neutrons.

If a fan draws 220 watts on a 120- volt circuit what is the current being drawn?
22. amperes
O 5.2 amperes
O 1.8 ampmes
15. amperes

Answers

Explanation:

here's the answer to your question

1. Find the temperature when the degrees of the Celsius scale will be one fifth of the corresponding degrees of the Fahrenheit scale

2. How much heat is necessary to warm 500g of water from 20°C to 65°C?​

Answers

Answer:

F = 9/5 C + 32     conversion from C to F

F = 9/5 * F/5 + 32

25 F = 9 F + 800

16 F = 800

F = 50  

Check:

C = 5/9 ( F - 32)  = 5/9 (50 - 32) = 10  as requested

Q = c m change in temp

Q = 1 cal/gm-deg C * 500 gm * 45 deg C = 22,500 calories

50 Fahrenheit heat required.

How much heat required?

Heat transfer is a discipline of thermal engineering that concerns the generation, use, conversion, and exchange of thermal energy  between physical systems.

F = 9/5 C + 32     conversion from C to F

F = 9/5 * F/5 + 32

25 F = 9 F + 800

16 F = 800

F = 50

The answer is 50 Fahrenheit.

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how does the siphon work​

Answers

Answer:

A simple siphon raises water over a crest and discharges it at a lower level.It works coninueasly due to pull of gravity.

Explanation:

Siphons are tubes which draw fluid over the rim of a tank to a lower point. After an initial pressure change to initiate the flow, siphons operate continuously due to the pull of gravity.

Working:

A simple siphon raises water over a crest and discharges it at a lower level. As water flows through a siphon, energy due to pressure and elevation is either lost to pipe friction or converted to velocity energy.

what weight is recorded by a scale when it is placed inside a lift which is in free fall? Enplain.​

Answers

There is no pressure of your feet on the scales, and no pressure of the floor on the scales, so the scales will read zero I hope this is right

Answer:

Explanation:

There is no pressure of your feet on the scales, and no pressure of the floor on the scales, so the scales will read zero*. Hence, your weight, in a freely falling lift is zero

A rocket travels vertically at a speed of 1200 km/h. The rocket is tracked through a telescope by an observer located 16km from the launching pad. Find the rate at which the angle between the telescope and the ground is increasing 3 min after lift-off. Round your answer to the nearest hundredth rad/hr

Answers

Answer:

w = 0.01 t⁻²   rad/h

Explanation:

Let's use trigonometry to find the elevation angle of the telescope, we assume that the rocket remains fixed in the telescope.

        tan θ = CO / CA

the adjacent leg is CA = 16 km = 16 10³ m

Let's use kinematics to find the height of the rocket

          v = y / t

          y = v t

this height is equal to the opposite leg

          CO = v t

     

we substitute

         tan θ = vt / 16

         tan θ = 1200/16 t

         tan θ = 75 t

         θ = tan⁻¹ ( 75 t )

speed is defined by

          w = dθ/dt

          w = [tex]\frac{1}{1 + (75 t)^2} \ 75[/tex]  

         

as time increases we can neglect the 1 of the denominator

          w = 1/75 t²

          w = 0.0133 t⁻²

Using three significant figures

           w = 0.01 t⁻²   rad/h

for this answer the time must be given in hours

write any two uses of a wedge.​

Answers

Answer: two uses of a wedge can be to tighten things as well as to lift things.

Explanation: because that is some things wedges (a mechanical tool) can do.

En un rio una Onda viaja con una velocidad de propagación de 50 m/s con una longitud de Onda de 40 metros. Hallar la frecuencia de la Onda.

Answers

Answer:

Frequencia = 1.25 Hz

Explanation:

Dados los siguientes datos;

Velocidad = 50 m/s Longitud de onda = 40 metros

Para encontrar la frecuencia de la onda;

Matemáticamente, la velocidad de una onda viene dada por la fórmula;

[tex] Velocidad = Longitud \; de \; onda * Frequencia [/tex]

Haciendo de la frecuencia el tema de la fórmula, tenemos;

[tex] Frequencia = \frac {Velocidad}{Longitud \; de \; onda} [/tex]

Sustituyendo en la fórmula, tenemos;

[tex] Frequencia = \frac {50}{40} [/tex]

Frequencia = 1.25 Hz

Which choice shows the correct sequence of features formed by continued wave erosion?

Answers

Answer:

Wave-cut cliff, sea arch, sea stacks

Explanation:

The effect of a wave erosion is made obvious by the structures formed by the wave action.

The high areas of land adjacent to the incoming wave develop the early features or the formation of wave action, which includes the wave-cut cliff

The continuous undercutting of the cliff by the wave results in the formation of the wave cut platform

The effect of the wave further on a cliff, results in the formation of a sea arch and finally a sea stack

Therefore, the correct sequence is the wave-cut cliff, sea arch, sea stacks

A sound frequency 100Hz and wavelength 3.34m is travelling through air, calculate the Velocity of sound in air.

Answers

Answer:

334m/s

Explanation:

If you take the data you gave and insert it into the equation f=v/λ the frequency would come out to be 3.34m

334 m/s is  the Velocity of sound in air.

What is the velocity of a wave?

Wave velocity in common usage refers to speed, although, properly, velocity implies both speed and direction.

The velocity of a wave is equal to the product of its wavelength and frequency (number of vibrations per second) and is independent of its intensity.

Mathematically , v=fλ

According to the question,

Sound frequency (f)  = 100Hz

Wavelength (λ)= 3.34m

Computing the values in the formula,

v=fλ

v = 100Hz x 3.34m

v= 334m/s

Therefore,

Velocity of sound in air is 334 m/s.

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help me guys, i am illiterate
if the mass of the moon 7.2*10^22 kg and and the radius is 1.7*10^6m , what will be the acceleration due to gravity of the moon ? what will be the weight of a person of 60 kg mass on the surface of moon ?

Answers

Answer:

A. 1.66 N/Kg or m/s²

B. 99.6 N

Explanation:

A. Determination of the acceleration due to gravity of the moon.

Mass of the moon (Mₘ) = 7.2×10²² Kg

Radius of the moon (rₘ) = 1.7×10⁶ m

Gravitational constant (G) = 6.67×10¯¹¹ Nm²/Kg²

Acceleration due to gravity of the moon (gₘ)

gₘ = GMₘ / rₘ²

gₘ = (6.67×10¯¹¹ × 7.2×10²²) / (1.7×10⁶)²

gₘ = 1.66 N/Kg

Acceleration due to gravity on the moon is 1.66 N/Kg or m/s²

B. Determination of the weight of a 60 kg person on the moon.

Acceleration due to gravity of the moon (gₘ) = 1.66 N/Kg

Mass of person (m) = 60 Kg

Weight on the moon (Wₘ) =?

Wₘ = m × gₘ

Wₘ = 60 × 1.66

Wₘ = 99.6 N

Thus, the weight of a 60 kg person on the moon is 99.6 N

Why does a small piece of steel rod sinks while a large steel oil tanker floats?

Plss help thanks! pls include EXPLANATION and EXAMPLES that I can proof to people that has no knowledge ​

Answers

Answer:

Too what i know its because of the air

Explanation:

The steel rod is more dense and doesnt have air whil'st the oil tanker is less dense with lots of air

a ball was changed vertically upwards with kinetic energy 200 joule what will be the total energy and Midway​

Answers

Answer:

Part 1; The total energy = Constant = 200 J

Part 2; Midway, the potential energy = The kinetic energy = 100 J

Explanation:

Part 1

According to the first law of thermodynamics, energy is neither created nor destroyed but changed from one form to another

The total (mechanical) energy = Potential energy + Kinetic energy = Constant

The kinetic energy given to the ball changed vertically up = 200 J

Potential energy = Mass, m × Gravity, g × Height, h

Given that the mass m of the ball and the acceleration due to gravity, g, remain the same, we have;

Potential energy ∝ The height of the ball

The potential energy at ground level = 0 J (Height , h = 0)

∴ The total (mechanical) energy = 0 J + 200 J = 200 J

At the maximum height, the ball momentarily stops, and the kinetic energy = 0 J

Therefore;

The potential energy of the ball at the maximum height, [tex]h_{max}[/tex], [tex]P.E._{max}[/tex] = 200 J

∴  [tex]P.E._{max}[/tex] = m·g·[tex]h_{max}[/tex] = 200 J

Part 2

At midway we have, the height, h = ([tex]h_{max}[/tex])/2

Therefore, [tex]P.E._{Midway}[/tex] = (m·g·([tex]h_{max}[/tex]))/2 = ([tex]P.E._{max}[/tex])/2 = (200 J)/2 = 100 J

The potential energy midway = 100 J

The  remaining 200 J - 100 J = 100 J is the kinetic energy remaining in the ball

The kinetic energy midway = 100 J

Therefore, the total energy midway = 100 J + 100 J = 200 J

An astronaut on Pluto attaches a small brass ball to a 1.00-m length of string and makes a simple pendulum. She times 10 complete swings in a time of 257 seconds. From this measurement she calculates the acceleration due to gravity on Pluto. What is her result

Answers

Answer:

The acceleration due to gravity at Pluto is 0.0597 m/s^2.

Explanation:

Length, L = 1 m

10 oscillations in 257 seconds

Time period, T = 257/10 = 25.7 s

Let the acceleration due to gravity is g.

Use the formula of time period of simple pendulum

[tex]T = 2\pi\sqrt{\frac{L}{g}}\\\\25.7 = 2 \times 31.4\sqrt{\frac{1}{g}}\\\\g = 0.0597 m/s^2[/tex]

Tính công của dòng điện

Answers

Answer:

CG gh sure er go b vh pxuh FPI OO c AM h kh

if a person buys 10 kg apples in himalayan region and sells in terai region will he get profit or loss. why?​

Answers

Answer:

he will be in profit

Explanation:

Himalayan region are high above the sea level so the gravity will be less there compared to the Terai region

Terai lies way below he Himalayan region so the pull of gravity will be more compared to Himalayan region

that's why he will be in profit but not loss

Question in the picture please help me...
Show all steps please....​

Answers

Answer: i)A to B : (ice) freezing

ii) B to C (water) boiling

C to D  (steam) evaporating

explanation:  0° is the freezing point of water  when temperature increases from 0° the water starts melting. As 100° is the boiling point of water so at 100° the water  completely melts and it starts boiling during boiling water changes into steam(water vapour) and it evaporates

The mass of earth 6*10^24kg its radius is 6.4*10^3km now calculate due to gravity on earth

Answers

Answer:

Explanation:

in your textbook, they have a formula like this:

g=mass of earth*G/R^2

G=6.67*10^-11

apply to this

we have g=6*10^2*4*6.67*10^-11/(6.4*10^3*1000)^2=9.78

calculate the potential energy stored in a meta ball of mass of 80 kg kept at a height of 15m from the earth surface . What will be the potential energy when the metal ball is kept on the earth surface Take (g- 9.8 m/s] ​

Answers

Answer:

11760 J

Explanation:

cuz potential engery is PE = MHG

SO 80×15×9.8= 11760 J

Answer:

11769j

Explanation:

here,

mass(m)=80 kg

height(h)=15m

acceleration due to gravity(g)=9.8m/s^2

now,

potential energy = m×g×h

= 80×9.8×15

= 11760j

an electron is moving at 3.6 x 10^3 m/s. a photon with what wavelength would have the same momentum????

Answers

Answer:

The wavelength of the photon that would have the same momentum as the electron is 202.2180996 nm

Explanation:

The velocity of the electron, v = 3.6 × 10³ m/s

The momentum of an electron, [tex]p_e[/tex] = m × v

Where;

v = The mass of the electron = 9.109 × 10⁻³¹ kg

∴ [tex]p_e[/tex] = 9.109 × 10⁻³¹ kg × 3.6 × 10³ m/s = 3.27924 × 10⁻²⁷ kg·m/s

According to the de Broglie equation, the momentum of a photon, p, is given as follows;

p = h/λ

Where;

h = 6.63 × 10⁻³⁴ J·s

λ = The wavelength of the photon

∴ λ = h/p

According to the question, we have;

p = [tex]p_e[/tex] = 3.27924 × 10⁻²⁷ kg·m/s

∴ λ = 6.63 × 10⁻³⁴ J·s/(3.27924 × 10⁻²⁷ kg·m/s) = 2.02180993 × 10⁻⁷ m

The wavelength of the photon, λ = 2.02180993 × 10⁻⁷ m = 202.2180993 × 10⁻⁹ m = 202.2180993 nm.

What is the apparent deflection of a light beam in an elevator which is 2.7 m wide if the elevator is accelerating downward at 9.8 m/s^2?

Answers

Answer:

[tex]X=3.37561*10^{-16}[/tex]

Explanation:

From the question we are told that:

Width [tex]w=2.7m[/tex]

Acceleration [tex]a=9.8m/s^2[/tex]

Generally the equation for The apparent deflection is mathematically given by

X= 0.5 *g*t^2

Where

[tex]t=\frac{width}{Velocity of light}[/tex]

[tex]t=\frac{2.5}{3*10^8}[/tex]

[tex]t=8.3*10^{-9}[/tex]

Therefore

[tex]X= 0.5 *9.8*(8.3*10^{-9})^2[/tex]

[tex]X=3.37561*10^{-16}[/tex]

: 1 khối khi lý tưởng nhận được nhiệt lượng 200J, khi đó khí nở ra đẩy pittong bằng 1 công 80J.
Vậy nội năng Của khí là bao nhiêu

Answers

Answer:

DU = 120 Joules

Explanation:

Given the following data;

Quantity of energy = 200 J

Work = 80 J

To find the change in internal energy;

Mathematically, the change in internal energy of a system is given by the formula;

DU = Q - W

Where;

DU is the change in internal energy.

Q is the quantity of energy.

W is the work done.

Substituting into the formula, we have;

DU = 200 - 80

DU = 120 Joules

Which law states that absolute zero cannot be reached?

Answers

Assuming you mean temperature

Answer: The third law of thermodynamics

Wat is acceleration!!!!!​

Answers

Answer:

Acceleration is the rate of change of velocity with time.its system international unit is meters per second square.

I hope this helps

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