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## Karnataka 1st PUC Physics Previous Year Question Paper March 2019

**Mangalore District **

**First PUC Annual Examination, March 2019**

Time : 3.15 Hours

Maximum Marks: 70

General Instructions:

1. All parts are compulsory.

2. Answers without relevant diagram / figure / circuit wherever necessary will not carry any marks.

3. Numerical problems should be solved with relevant formulae.

Part – A

I Answer the following questions. ( 10 × 1 = 10 )

Question 1.

Name the system of units accepted internationally.

Question 2.

Define null vector.

Question 3.

Give on example for conservative force.

Question 4.

Write an expression for moment of inertia of a solid sphere of radius R and mass M about its diameter.

Question 5.

Define angular acceleration

Question 6.

What is meant by elasticity of a body?

Question 7.

How does the fractional change in length of a rod varies with its change in temperature?

Question 8.

State zeroth law of thermodynamics

Question 9.

Define mean free path of a gas molecule.

Question 10.

What is a node in stationary waves?

Part – B

II. Answer any FIVE of the following Questions. ( 5 × 2 = 10 )

Question 11.

Name the strongest and weakest fundamental forces in nature.

Question 12.

Write any two applications of dimensional analysis.

Question 13.

Write any two differences between distance and displacement.

Question 14.

Mention any two factors on which the centripetal acceleration depends.

Question 15.

How does the linear momentum of a body varies with its mass and velocity?

Question 16.

State Pascal’s law. Name any one device which works on the principle of Pascal’s law.

Question 17.

State and explain Boyle’s law.

Question 18.

What is periodic motion? Give an example.

Part – C

III. Answer any FIVE of the following questions. ( 5 × 3 = 15 )

Question 19.

Explain triangle method of addition of two vectors.

Question 20.

Write any three advantages of friction

Question 21.

Define work done by a force. Under what conditions the work done by a force is maximum and minimum?

Question 22.

When does the rigid body is said to be in mechanical equilibrium? Write the conditions for the equilibrium of a rigid body.

Question 23.

Derive an expression for acceleration due to gravity on the surface of the earth in terms of mass of the earth and gravitational constant.

Question 24.

State and explain Hook’s law and hence define modulus of elasticity.

Question 25.

What is meant by viscosity? How does the viscosity change with rise of temperature in case of (i) liquids and

(ii) gases?

Question 26.

What is radiation? Mention any two properties of thermal radiations.

Part – D

IV. Answer any TWO of the following Questions. ( 2 × 5 = 10 )

Question 27.

What is meant by velocity – time graph? Derive the equation x = v_{0}t + \(\frac{1}{2}\) at^{2} from velocity – time graph

Question 28.

Define elastic potential energy. Derive an expression for potential energy of a spring.

Question 29.

Derive an expression for kinetic energy of a rolling body.

V. Answer any TWO of the following questions. ( 2 × 5 = 10 )

Question 30.

Explain the working of Carnot engine with the help of PV diagram.

Question 31.

Derive an expression for time period of oscillation of a simple pendulum

Question 32.

Show that only odd harmonics are present in vibrations of air column in closed pipe.

VI. Answer any THREE of the following questions. ( 3 × 5 = 15 )

Question 33.

A Cricket ball is thrown at a speed of 28 ms^{-1} in the direction 30° above the horizontal. Calculate (a) maximum

height reached by the projectile and (b) horizontal range of the projectile. (Given: Acceleration due to gravity = 9.8 ms^{-2})

Question 34.

A constant force acting on a body of mass 3.0 kg changes its speed from 2.0 ms^{-1} to 3.5 ms^{-1} in 25 second. If the direction of the motion of the body remains unchanged, find the magnitude and direction of the force?

Question 35.

An artificial satellite revolves around the earth with an orbital velocity of 5.92 kms^{-1}. Calculate height of the satellite from the earth’s surface. (Given: Radius of the earth = 6380 km Acceleration due to gravity of earth = 9.8 ms^{-2}).

Question 36.

A copper block of mass 2.5 kg is heated in a furnace to a temperature of 500°C and then placed on a large ice block at a temperature of 0°C. Calculate the maximum amount of ice that can melt? (Given: Specific he: t of copper = 390 Jkg^{-1}k^{-1} Latent heat of fusion of ice = 3.35 × 105 Jkg^{-1})

Question 37.

A transverse harmonic wave travelling along positive X-axis on a stretched string is described by Y(x, t) = 0.03 sin(36t – 1.8x + \(\frac{\pi}{4}\)) where X and Y are in metre and t is in second. Calculate (a) amplitude (b) initial phase (c) frequency and (d) speed of the wave.

**Bangalore North District**

**First PUC Annual Examination, March 2019**

Time : 3.15 Hours

Maximum Marks: 70

General Instructions:

1. All parts are compulsory.

2. Answers without relevant diagram / figure / circuit wherever necessary will not carry any marks.

3. Numerical problems should be solved with relevant formulae.

Part – A

I. Answer the following questions. ( 10 × 1 = 10 )

Question 1.

How many kilograms in one unified atomic mass unit?

Question 2.

State the law of triangle of addition of two vectors.

Question 3.

State Aristotle’s fallacy.

Question 4.

Name the type of energy stored in a stretched or compressed spring.

Question 5.

Give an example for Torque or Moment of couple.

Question 6.

Write the aim of Cavendish experiment in Gravitation.

Question 7.

How does strain depends on stress?

Question 8.

Mention the value of steam point of water in Fahrenheit scale.

Question 9.

Which quantity is kept constant in Adiabatic process.

Question 10.

The function y = log(ωt). The displacement y increases monotonically with time t, is it periodic function or Non periodic function.

Part – B

II. Answer any FIVE of the following Questions. ( 5 × 2 = 10 )

Question 11.

Name any two fundamental forces in nature.

Question 12.

Define accuracy in the measurement. How does accuracy depends on precision in the measurement?

Question 13.

Distinguish between speed and velocity.

Question 14.

State and explain Newton’s first law of motion.

Question 15.

Mention the relation between linear momentum and angular momentum with usual meanings.

Question 16.

Write any two practical applications of Pascal’s law.

Question 17.

Give any two Assumptions of Kinetic theory of gases.

Question 18.

How does the period of oscillation of a pendulum depends on mass of the bob and length of the pendulum.

Part – C

III. Answer any FIVE of the following questions. ( 5 × 3 = 15 )

Question 19.

Deduce the expression for Horizontal range of a projectile and for what angle of projection horizontal range becomes maximum?

Question 20.

Write any three laws of friction.

Question 21.

Deduce the work-energy theorem for a constant force.

Question 22.

Discuss the motion of centre of mass.

Question 23.

Name the three types of moduli of elasticity.

Question 24.

What is capillary rise? Write the expression for height of capillary rise in the capillary tube with usual meanings.

Question 25.

Obtain the expression for Thermal stress.

Question 26.

Show that the specific heat capacity of a solid is equal to three times that of Gas constant.

[C = 3R]

Part – D

IV. Answer any TWO of the following Questions. ( 2 × 5 = 10 )

Question 27.

What is velocity – time graph? Deduce x = v_{0}t + \(\frac{1}{2}\) at^{2} by using velocity-time graph.

Question 28.

State and illustrate the law of conservation of linear momentum for any two colliding particles in a closed system.

Question 29.

State and explain parallel axes and perpendicular axes theorems of moment of inertia.

V. Answer any TWO of the following questions. ( 2 × 5 = 10 )

Question 30.

State and explain the laws of thermal conductivity and hence mention the SI Unit of coefficient of thermal conductivity.

Question 31.

Deduce the expression for energy stored in a body executing simple harmonic motion.

Question 32.

Discuss the mode of vibration of air columns in a closed pipe and hence define the fundamental frequency of vibration.

VI. Answer any THREE of the following questions. ( 3 × 5 = 15 )

Question 33.

A stone of mass 0.25 kg tied to the end of a string is whirled round in a circle of radius 1.5 m with a speed of 40 revolutions per minute in a horizontal plane. What is the tension in the string?

Question 34.

A pump on the ground floor a building can pump up water to fill a tank of volume 30 m^{3} in 15 minutes. If the tank is 40 m above the ground and efficiency of the pump is 30%. How much of electrical power is consumed by the pump?

Question 35.

If two spheres of equal masses with their centres 0.2 m apart attract each other with a force of 1 x 10^{-6} kg wt. What should be the value of their masses?

Given : g = 9.8 ms^{-2} and G = 6.67 × 10^{-11} Nm^{2} kg^{-2}.

Question 36.

The sink in Carnot’s heat engine is at 300 K and has efficiency 0.4. If the efficiency of the engine is to be increased to 0.5. Find by how many Kelvin the temperature of the source should be increased.

Question 37.

A train is moving at a speed of 72 Kmph towards a station sounding a whistle of frequency 640 Hz. What is the apparent frequency of the whistle as heard by a man standing on the platform when train approaches to him.

Given : Speed of sound = 340 ms^{-1}.

**Bangalore South District**

**First PUC Annual Examination, March 2019**

Time : 3.15 Hours

Maximum Marks: 70

General Instructions:

1. All parts are compulsory.

2. Answers without relevant diagram / figure / circuit wherever necessary will not carry any marks.

3. Numerical problems should be solved with relevant formulae.

Part – A

I. Answer the following questions. ( 10 × 1 = 10 )

Question 1.

Write the dimensional formula for force.

Question 2.

Write SI unit of power.

Question 3.

What is Projectile motion?

Question 4.

Write relation between angular velocity and linear velocity.

Question 5.

Write expression for acceleration due to gravity at a height h from the surface of earth.

Question 6.

Define stress.

Question 7.

Define angle of contact.

Question 8.

Write ideal gas equation for one mole of gas.

Question 9.

State zeroth law of thermodynamics.

Question 10.

State law of equipartition of energy.

Part – B

II. Answer any FIVE of the following Questions. ( 5 × 2 = 10 )

Question 11.

Name any two fundamental forces in nature.

Question 12.

Write any two applications of dimensional analysis.

Question 13.

A body gets displacement of 5m in 2s. What is the average velocity?

Question 14.

Define scalar product of two vectors.

Question 15.

What is kinetic friction? Write the expression.

Question 16.

Define specific heat capacity of a substance.

Question 17.

Write any two difference between isothermal process and adiabatic process.

Question 18.

Define frequency and period of oscillation.

Part – C

III. Answer any FIVE of the following questions. ( 5 × 3 = 15 )

Question 19.

A body moving in uniform circular motion, Derive centripetal acceleration a_{e} = \(\frac{v^{2}}{r}\).

Question 20.

State Newton’s second law of motion. Hence derive F = ma.

Question 21.

State work energy theorem with proof.

Question 22.

Show that kinetic energy of rotating body is \(\frac{1}{2}\) Iω^{2}.

Question 23.

State Kepler’s laws of planetory motion.

Question 24.

Calculate \(\frac{C_{p}}{c_{v}}\) for monatomic gas.

Question 25.

Write stress-strain curve for a metal. What is proportional limit and yield point.

Question 26.

State Bernoulli’s theorem and write the equation.

Part – D

IV. Answer any TWO of the following Questions. ( 2 × 5 = 10 )

Question 27.

Derive the equation x = v_{0}t + \(\frac{1}{2}\) at^{2} using v-t graph.

Question 28.

State and explain law of conservation of momentum with proof.

Question 29.

State and explain parallel axis and perpendicular axis theorem.

V. Answer any TWO of the following questions. ( 2 × 5 = 10 )

Question 30.

Explain working of Carnot’s heat engine.

Question 31.

Derive an expression for energy of a body which is in S.H.M.

Question 32.

What is Doppler effect of sound? Derive expression for apparent frequency of sound when source is moving away from stationary listener.

VI. Answer any THREE of the following questions. ( 3 × 5 = 15 )

Question 33.

A body is projected by making an angle 30° with horizontal with a velocity of 39.2 ms^{-1}. Find

A. Time of flight (T)

B. Range (R)

C. Maximum height (H)

Question 34.

A body of mass 5 kg moving with a velocity of 6 ms^{-1} collide with another body of mass 2 kg which is at rest. After wards they move in the same direction as before. If the velocity of the body of mass 2 kg is 10 ms^{-1}. find the velocity and kinetic energy of the body of mass 5 kg.

Question 35.

Find the potential energy of a system of four particles each of mass 5 kg placed at the vertices of a square of side 2m.

Question 36.

Two identical bars each of length L = 0.1 m and area A = 0.02 m^{2}. One is iron of thermal conductivity K_{1} = 79 W m^{-1 }K^{-1} and another of brass of thermal conductivity K_{2} = 109 W m^{-1} K^{-1} are soldered end to end. Free end of iron bar is at 373K and of brass bar is at 273K. Find the temperature at junction of two bars.

Question 37.

A wave travelling in a string is described by an equation y(x, t) = 0.005 sin (80x – 3t) all are in SI unit. Find

a) amplitude (A)

b) Wave length (λ)

c) Period (T)

**Dharwad District**

**First PUC Annual Examination, February 2019**

Time : 3.15 Hours

Maximum Marks: 70

General Instructions:

2. Answers without relevant diagram / figure / circuit wherever necessary will not carry any marks.

3. Numerical problems should be solved with relevant formulae.

Part – A

I. Answer the following questions. ( 10 × 1 =10 )

Question 1.

Define acceleration.

Question 2.

What does slope of velocity – time graph represent?

Question 3.

For what angle of projection, does the range of a projectile is maximum?

Question 4.

Stale Work – Energy theorem.

Question 5.

Mention an expression for moment of inertia of a thin, circular ring of radius ‘R’ and mass ‘M’ about an axis passing through its diameter.

Question 6.

Mention the value of universal gravitational constant.

Question 7.

Of rubber and steel, which is more elastic?

Question 8.

What happens lo viscosity of a liquid, when it is heated?

Question 9.

State first law of thermodynamics.

Question 10.

Mention the number of degrees of freedom of a mono atomic gas.

Part – B

II. Answer any FIVE of the following Questions. ( 5 × 2 = 10 )

Question 11.

Mention any two basic forces in nature.

Question 12.

A pebble of mass 0.05 kg is thrown vertically upwards. Give the direction of the net force on the pebble

(a) During its upward motion (b) During its downward motion

Question 13.

Mention the conditions for equilibrium of a rigid body.

Question 14.

State and explain Newton’s law of gravitation.

Question 15.

Distinguish between heat capacity and specific heat capacity.

Question 16.

Convert 100°C into Fahrenheit temperature.

Question 17.

Define period and frequency of oscillation.

Question 18.

Distinguish between longitudinal waves and transverse waves.

Part – C

III. Answer any FIVE of the following questions. ( 5 × 3 = 15 )

Question 19.

Check the correctness of an equation V – V_{0} = at using dimensional analysis (symbols have usual meaning).

Question 20.

Mention any three advantages of friction.

Question 21.

Derive an expression for potential energy of a stretched spring.

Question 22.

Explain law of conservation of angular momentum in case of a person sitting in a rotating chair.

Question 23.

Define Young’s modulus. Mention an expression for Young’s modulus of a wire and explain the symbols used.

Question 24.

Derive an expression for liquid pressure at a point inside the liquid.

Question 25.

State and explain Dalton’s law of partial pressures.

Question 26.

Mention Newton’s formula for speed for sound in gases and explain Laplace’s connection to Newton’s formula.

Part – D

IV. Answer any TWO of the following Questions. ( 2 × 5 = 10 )

Question 27.

Derive x = v_{0}t + \(\frac{1}{2}\) at^{2} using velocity – time graph.

Question 28.

Derive an expression for centripetal acceleration.

Question 29.

State and verify law of conservation of linear momentum in case of a system of two bodies.

V. Answer any TWO of the following questions. ( 2 × 5 = 10 )

Question 30.

What is meant by acceleration due to gravity? Derive an expression for variation of acceleration due to gravity with height from earth’s surface.

Question 31.

What is heat engine? With schematic diagram, explain the parts of heat engine.

Question 32.

Derive an expression for total energy in simple harmonic motion.

VI. Answer any THREE of the following questions. ( 3 × 5 = 15 )

Question 33.

A cricket ball is thrown at a speed of 50 ms^{-1} in a direction making an angle 30° with the horizontal, calculate time of flight and maximum height. (Given y = 9.8 ms^{-2})

Question 34.

A pump on the ground floor of a building can pump up water to fill a tank of volume 30m^{3} in 15 minutes. If the tank is 40 m above the ground and the efficiency of the pump is 30%. How much electric power is consumed by the pump? (Density of water is 10^{3 }kg m^{-3})

Question 35.

The angular speed of a motor wheel is increased from 1200 rpm to 3120 rpm in 16 seconds.

(i) What is its angular acceleration?

(ii) How many revolutions does the wheel make during this time?

Question 36.

A body cools from 80°C to 50°C in 5 minutes. Calculate the time it takes to cool from 60°C to 30°C. The temperature of the surrounding is 20°C.

Question 37.

A train, standing at die outer signal of a railway station blows a whistle of frequency 400 Hz in still air. What is the frequency of the whistle for a platform observer when die train

(a) Approaches the platform with a speed of 10 ms^{-1}.

(b) Recedes from the platform with a speed of 10 ms^{-1}

(c) What is the speed of sound in each case? Speed of sound in still air can be taken as 340 ms^{-1}.

**Mysore District**

**First PUC Annual Examination, February 2019**

Time : 3.15 Hours

Maximum Marks: 70

General Instructions:

2. Answers without relevant diagram / figure / circuit wherever necessary will not carry any marks.

3. Numerical problems should be solved with relevant formulae.

Part – A

I. Answer the following questions. ( 10 × 1 = 10 )

Question 1.

Write the dimensional formula for Pressure.

Question 2.

When does the circular motion become uniform?

Question 3.

What is the amount of work done by the gravitational force on the body moving on the horizontal plane?

Question 4.

What is elastic collision?

Question 5.

Give one example for elastomers.

Question 6.

What is thermal stress?

Question 7.

Define mean free path of the molecule in the gas.

Question 8.

Where does Kinetic energy of the oscillating particle become maximum?

Question 9.

What is resonance?

Question 10.

Give the value of phase difference between the particles of adjacent loop of stationary wave.

Part – B

II. Answer any FIVE of the following Questions. ( 5 × 2 = 10 )

Question 11.

Name any two fundamental forces of nature.

Question 12.

Mention any two sources of systematic error.

Question 13.

Draw position time graph for the particle having zero acceleration.

Question 14.

Write the equation for maximum horizontal range in projectile motion and explain the terms.

Question 15.

Mention any two methods of reducing friction.

Question 16.

Mention the conditions for the body in mechanical Equilibrium.

Question 17.

State and explain Hooke’s law.

Question 18.

What are extensive thermo dynamical variables? Give one example.

Part – C

III. Answer any FIVE of the following questions. ( 5 × 3 = 15 )

Question 19.

Obtain the equation for maximum height in projectile motion.

Question 20.

Derive \(\overrightarrow{\boldsymbol{F}}=m \overrightarrow{\boldsymbol{a}}\) with usual notations.

Question 21.

Prove the work-energy theorem in the case of constant force.

Question 22.

Obtain the equation for moment of couple.

Question 23.

Derive equation for acceleration clue to gravity on the surface of the earth.

Question 24.

Show that volume co-efficient of expansion of ideal gas is inversely proportional to absolute temperature.

Question 25.

Show that C_{v} = \(\frac{3}{2}\) R for mono atomic gas.

Question 26.

Give any three differences between progressive wave and stationary wave.

Part – D

IV. Answer any TWO of the following Questions. ( 2 × 5 = 10 )

Question 27.

Derive equation for centripetal acceleration.

Question 28.

Prove “law of conservation of mechanical energy” for freely falling body.

Question 29.

Obtain equation for Kinetic energy of rolling motion.

V. Answer any TWO of the following questions. ( 2 × 5 = 10 )

Question 30.

State and prove Bemaulli’s theorem.

Question 31.

What is isothermal process? Obtain equation for work done in isothermal process.

Question 32.

What is closed pipe? Show that modes of vibration in closed pipe are odd harmonics.

VI. Answer any THREE of the following questions. ( 3 × 5 = 15 )

Question 33.

A Car moving along a straight road with speed of 144 Kmh^{-1} is brought to a stop within a distance of 200 m. What is the retardation of the car and how long does it take to come to rest?

Question 34.

A circular racetrack of radius 200 m is banked at the angle of 10°. If the coefficient of friction between the wheels of race car and the road is 0.15, what is the

a) optimum speed of the race car to avoid wear and tear on its tyres?

b) maximum permissible speed to avoid slipping? [Given : Acceleration due to gravity on the earth = 9.8 ms-2]

Question 35.

If the weight of a 4 kg mass on the surface of the earth is 39.2 N, calculate the acceleration due to gravity of earth at

a) 32 km height from the surface of the earth.

b) 16 km depth from the surface of the earth. [Given : Radius of earth = 6400 km]

Question 36.

A copper block of mass 2.5 kg is heated in a furnace to a temperature of 500°C and then placed on a large ice block. What is the maximum amount of ice that can melt?

(Given: Specific heat of copper = 0.39 × 10^{3} Jkg^{-1}K^{-1} Latent Heat of fusion of water = 335 x 10^{3} Jkg^{-1})

Question 37.

A body oscillates with SHM according to the equation (in SI units)

x = 5 cos (3πt + \(\frac{\pi}{4}\))

Calculate:

(a) frequency of oscillation

(b) amplitude of oscillation

(c) Displacement of oscillation at t= 1s

**Belgaum District**

**First PUC Annual Examination, March 2019**

Time : 3.15 Hours

Maximum Marks: 70

General Instructions:

2. Answers without relevant diagram / figure / circuit wherever necessary will not carry any marks.

3. Numerical problems should be solved with relevant formulae.

Part – A

I. Answer the following questions. ( 10 × 1 = 10 )

Question 1.

Write the number of significant figures in 287.5 m.

Question 2.

Give example for a vector multiplied by scalar.

Question 3.

When work done is said to be maximum?

Question 4.

Which law of motion is used to explain rocket propulsion?

Question 5.

Write S. I. unit of moment of inertia.

Question 6.

Which is more elastic, rubber or steel?

Question 7.

Define coefficient of volume expansion in solids.

Question 8.

State Zeroth law of thermodynamics.

Question 9.

How many degrees of freedom are there in diatomic gases?

Question 10.

What is Doppler’s effect?

Part – B

II. Answer any FIVE of the following Questions. ( 5 × 2 = 10 )

Question 11.

Name any two basic forces in nature.

Question 12.

Mention any two uses of dimension analysis.

Question 13.

Draw velocity time graph of

a) a body starting from rest and moving with uniform acceleration.

b) a body moving with uniform negative acceleration.

Question 14.

Mention the expression for magnitude of two vectors and explain terms.

Question 15.

What is the importance of centre of mass of system of particles?

Question 16.

Define Poisson’s ratio and write the formula for it.

Question 17.

What is meant by streamline flow and turbulent flow?

Question 18.

What are damped oscillations? Give one example.

Part – C

III. Answer any FIVE of the following questions. ( 5 × 3 = 15 )

Question 19.

Obtain an expression for range of a projectile.

Question 20.

Mention types of friction.

Question 21.

Distinguish between elastic and inelastic collision.

Question 22.

State and explain the theorem of perpendicular axes.

Question 23.

Derive, the relation between acceleration due to gravity and gravitational constant.

Question 24.

Arrive at an expression for pressure inside a liquid.

Question 25.

What is latent heat? On what factors does it depend? Give its S.I. unit.

Question 26.

State the assumptions of kinetic theory of gases.

Part – D

IV. Answer any TWO of the following Questions. ( 2 × 5 = 10 )

Question 27.

Define centripetal acceleration and obtain expression for it

Question 28.

State Newton’s second law of motion and hence derive F = ma where symbols have usual meanings.

Question 29.

Define torque show that torque equal to the rate of change of angular momentum of particle.

V. Answer any TWO of the following questions. ( 2 × 5 = 10 )

Question 30.

State and explain the Newton’ s law of cooling.

Question 31.

Derive expression for frequency and time period of oscillatory bob of simple pendulum.

Question 32.

Explain modes of vibration of air column in closed Pipe.

VI. Answer any THREE of the following questions. ( 3 × 5 = 15 )

Question 33.

A player throws a ball upwards with an initial speed of 29.4 ms^{-1}.

a) What is the velocity at the highest point of its path?

b) To what height does the ball rise and after how long does the ball return to the player’s hands?

Take g = 9.8 ms^{-2} Neglect air resistance.

Question 34.

A pump on ground floor of building can pump up water to fill a tank of volume 30 m^{3} in 15 minutes. If tank is 40m above the ground and efficiency of pump is 30%, how much electric power is consumed by the pump. Take g = 9.8ms^{-2}, ρ= 1000 kgm^{-3}.

Question 35.

Calculate the acceleration due to gravity

a) at height 16 km above the earth’s surface and

b) at depth 12.8 km below the surface of earth,

Given radius of earth is 6400 km acceleration due to gravity on the surface of earth = 9.8 ms^{-2}.

Question 36.

A Carnot’s engine whose efficiency is 30% takes heat from a source maintained at temperature of 600 K of it desired to have an engine of efficiency 50%; What should be the intake temperature for same exhaust (sink)?

Question 37.

A progressive wave described by Y(x, t) = 0.005 sin(80πt – 3πx) where x, y are in metre and ‘t’ is in second. Find the (a) amplitude (b) wave length (c) period and frequency of wave.