Students should refer to ICSE Class 10 Physics Question Paper solved Set H given below which will help them to prepare for the upcoming ICSE Physics exams. Students should read ICSE Physics Class 10 Books to make sure they are completely prepared and should also refer to ICSE Class 10 Physics Solutions to understand all questions and their answers.
ICSE Class 10 Physics Question Paper solved Set H
Answers to this paper must be written on the paper provided separately.
You will not be allowed to write during the first 15 minutes.
This time is to be spent in reading the Question Paper.
The time given at the head of this paper is the time allowed for writing the answers.
Section I is compulsory. Attempt any four questions from Section II.
The intended marks for questions or parts of questions are given in brackets [ ].
ICSE Class 10 Physics Question Paper solved Set H
SECTION – I (40 Marks)
(Attempt all Questions
(a) (i) Define 1 kgf.
(ii) How is it related to the S.I. unit of force ? 
(b) (i) What are non-contact forces ?
(ii) How does the distance of separation between two bodies affect the magnitude of the non-contact force between them ? 
(c) A boy of mass 30 kg is sitting at a distance of 2 m from the middle of a see-saw. Where should a boy of mass 40 kg sit so as to balance the sea-saw ? 
(d) (i) What is meant by the term ‘moment of force’ ?
(ii) If the moment of force is assigned a negative sign then will the turning tendency of the force be clockwise or anticlockwise ? 
(e) A ball is placed on a compressed spring. When the spring is released, the ball is observed to fly away.
(i) What form of energy does the compressed spring possess ?
(ii) Why does the ball fly away ? 
(a) (i) The force with which a mass of 1 kg is attracted towards the centre of the earth, due to the acceleration due to gravity is called 1 kgf.
(ii) 1 kgf = 1 kg × acceleration due to gravity = 1 kg × 9.8 ms–2 = 9.8 N
(b) (i) The forces which do act on bodies without being physically touched are called the non-contact forces.
(ii) The magnitude of non-contact forces acting between the two bodies is inversely proportional to the square of distance between the mass centres of the two bodies.
(c) Let ‘x’ be the distance of 40 kg boy from the middle of see-saw.
∴ Moments due to 40 kg boy = Moments due to 30 kg boy
40 kg × x = 30 kg × 2 m
∴ x = 30 kg × 2 m / 40 kg = 1.5 m
(d) (i) The turning effect of a force about a fixed point or a fixed axis is called moment of force.
(ii) Negative sign of the moment of force implies that turning tendency of the force is in anticlockwise direction.
(e) (i) The compressed spring possesses potential energy.
(ii) The potential energy of the spring on releasing changes to kinetic energy. It is the kinetic energy which makes the ball to fly away.
(a) (i) State the energy conversion taking place in a solar cell.
(ii) Give one disadvantage of using a solar cell.  (b) A body of mass 0.2 kg falls from a height of 10 m to a height of 6 m above the ground.
Find the loss in potential energy taking place in the body. [ g = 10 ms–2] 
( c ) (i) Define the term refractive index of a medium in terms of velocity of light.
(ii) A ray of light moves from a rare medium to a dense medium as shown in the diagram below. Write down the number of the ray which represents the partially reflected ray.
(d) You are provided with a printed piece of paper. Using this paper how will you differentiate between a convex lens and a concave lens ? 
(e) A ray of light incident at an angle of incidence ‘ i’ passes through an equilateral glass prism such that the refracted ray inside the prism is parallel to its base and emerges from the prism at an angle of emer gence ‘e’.
(i) How is the angle of emergence ‘e’ related to the angle of incidence ‘i’ ?
(ii) What can you say about the value of the angle of deviation in such a situation ? 
(a) (i) In a solar cell, the light energy directly changes to electric energy.
(ii) Solar cell does not produce electric energy during night or in darkness. (b) Loss in potential energy = mass × g × loss of height
= 0.2 kg × 10 ms–2 × 4 m = 8 J
( c ) (i) Refractive index of a medium is the ratio of velocity of light in vacuum or air to the velocity of light in a given medium.
(ii) Ray 2, represents partially reflected ray.
(d) Hold each of the lens 5 cm above the printed paper and look for the image. In case of convex lens the print appears enlarged. However, in case of concave lens, the print appears diminished.
(e) (i) Angle of incidence is equal to the angle of emergence.
(ii) The angle of deviation is minimum in this particular case.
(a) (i) What is meant by ‘Dispersion of light’ ?
(ii) In the atmosphere which colour of light gets scattered the least ?  (b) Which characteristic of sound will change if there is a change in
(i) its amplitude (ii) its waveform. 
( c ) (i) Name one factor which affects the frequency of sound emitted due to vibrations in an air column.
(ii) Name the unit used for measuring the sound level.  (d) An electrical appliance is rated at 1000 kVA, 220V. If the appliance is operated for 2 hours,
calculate the energy consumed by the appliance in :
(i) kWh (ii) joule
(e) Calculate the equivalent resistance between P and Q from the following diagram : 
(a) (i) The phenomenon due to which white light splits into component colours on passing through a prism is called dispersion of light.
(ii) Red colour scatters least in the atmosphere.
(b) (i) With the change in amplitude, the loudness of sound changes.
(ii) With the change in waveform the quality of sound changes.
( c ) (i) The length of vibrating air column affects its frequency. More the length of vibrating air column, lesser is its frequency.
(ii) Decibel (dB) is the unit used for measuring sound level.
(d) (i) Energy consumed in kWh = 1000 kVA × 2h = 2000 kWh.
(ii) Energy consumed in Joules = 1000 × 1000 VA × 2 × 3600 s = 7,200,000,000 J
(e) Resistance of two 10W resistance in series = 10 + 10 = 20W
∴ Equivalent resistance of 20W in parallel with 5W resistance
∴ Resistance between P and Q in series = 3Ω + 4Ω + 2Ω = 9Ω
(a) (i) What is an a.c. generator or Dynamo used for ? 
(ii) Name the principle on which it works.
(b) Differentiate between heat capacity and specific heat capacity. 
(c) A hot solid of mass 60 g at 100ºC is placed in 150 g of water at 20ºC. The final steady temperature recorded is 25ºC. Calculate the specific heat capacity of the solid. [Specific heat capacity of water = 4200 J kg–1ºC–1] 
(d) (i) What is the value of the speed of gamma radiations in air or vacuum ?
(ii) Name a material which exhibits fluorescence when cathode rays fall on it. 
(e) Give any two important sources of background radiation. 
(a) (i) Dynamo is used for conversation of mechanical energy into electric energy.
(ii) Principle of A.C. Generator : When a conductor is rotated in a magnetic field, the magnetic flux linked with it changes and e.m.f. is induced in the coil.
(b) Heat capacity is the amount of heat required to raise the temperature of a given mass of substance through 1 K or (1ºC).
Specific heat capacity is the amount of heat required to raise the temperature of 1 kg (or 1g) of a substance through 1K (1ºC).
(d) (i) The speed of gamma rays (g) is 3 × 108 ms–1.
(ii) Zinc sulphide, Barium platinocyanide show fluorescence when cathode rays fall on it.
(e) (i) The radioactive emissions given out by the earth.
(ii) Sources are K-40, C-14 and Radium contained inside our body.
ICSE Class 10 Physics Question Paper solved Set H
SECTION – II (40 Marks)
(Attempt any four questions from this Section)
(a) (i) Which of the following remains constant in uniform circular motion : Speed or Velocity or both ?
(ii) Name the force required for uniform circular motion. State its direction ? 
(b) (i) State the class of levers and the relative positions of load (L), effort (E) and fulcrum (F) in each of the following cases.
1. a bottle opener
2. Sugar tongs.
(ii) Why is less effort needed to lift a load over an inclined plane as compared to lifting the load directly ? 
(c) (i) A moving body weighing 400 N possesses 500 J of kinetic energy.
Calculate the velocity with which the body is moving. (g = 10 ms–2)
(ii) Under what condition will a set of gears produce –
1. a gain in speed
2. a gain in torque. 
(a) (i) Speed remains constant during uniform circular motion.
(ii) Centripetal force. It is always directed towards the centre of the circular path.
(b) (i) 1. In case of bottle opener the load (L) acts in the middle of metal crown, the fulcrum (F) at the edge of metal crown and effort (E) at the end of the handle. It is a lever of second order.
2. Sugar tongs is a lever of third order. The sugar cube at the ends of tongs acts as load (L), the effort (E) acts in the middle and fulcrum (F) acts at its end.
(ii) Here, mechanical advantage = 1/sin θ ⇒ sin θ = 1 / Mechanical advantage
If a body rises 1 m vertically, when it moves along the inclined plane by 100 m. Then sin θ = 1/100. Higher the magnitude of the gradient, more difficult, more difficult is the slop to climb and vice-versa. Thus keeping gradient as low as possible which helps in using lesser effort for lift a load over inclined plane as compared to lifting the load directly.
( c ) (i) Force a cting on body (F) = mg
400 N = m × 100 ms–2
∴ Mass of body (m) = 400 N ÷ 10 ms–2 = 40 kg.
Kinetic energy of body (KE) = 1/2 mv2
(a) (i) What is meant by the term ‘critical angle’ ?
(ii) How is it related to the refractive index of the medium ?
(iii) Does the depth of a tank of water appear to change or remain the same when viewed normally from above ? 
(b) A ray of light PQ is incident normally on the hypotenuse of a right angled prism ABC as shown in the diagram given alongside :
(i) Copy the diagram and complete the path of the ray PQ till it emerges from the prism.
(ii) What is the value of the angle of deviation of the ray ?
(iii) Name an instrument where this action of the prism is used. 
(c) A converging lens is used to obtain an image of an object placed in front of it.
The inverted image is formed between F2 and 2F2 of the lens.
(i) Where is the object placed ?
(ii) Draw a ray diagram to illustrate the formation of the image obtained. 
(a) (i) The angle of incidence in a denser medium for which angle of refraction in rarer medium is 90º is called critical angle.
(ii) Refractive index (m) = 1/sin C
(iii) The depth of tank remains same when viewed normally from above.
(ii) The ray deviates through 180º.
(iii) Binoculars use this action of right angled prism.
(c) (i) The object is anywhere between 2F1 and infinity.
(a) (i) What is meant by Resonance ?
(ii) State two ways in which Resonance differs from Forced vibrations. 
(b) (i) A man standing between two cliffs pr oduces a sound and hea rs two successive echoes at intervals of 3 s and 4 s respectively. Calculate the distance between the two cliffs. The speed of sound in the air is 330 ms–1.
(ii) Why will an echo not be hears when the distance between the source of sound and the reflecting surface is 10 m ? 
(c) The diagram alongside shows the displacement-time graph for a vibrating body.
(i) Name the type of vibrations produced by the vibrating body.
(ii) Give one example of a body producing such vibrations.
(iii) Why is the amplitude of the wave gradually decreasing ?
(iv ) What will happen to the vibrations of the body after some time ?
(a) (i) The phenomenon due to which the natural frequency of a given body corresponds to the frequency of sound impressed on it, such that it rapidly starts vibrating is called resonance.
(ii) 1. The resonance takes place only when the natural frequency of a given body is equal to the frequency of sound impressed on it, whereas during forced vibration a body is forced to vibrate with the frequency of sound impressed on it.
2. Loud sound is produced during resonance, but not in case of forced vibrations.
(b) (i) Distance between two cliffs = v x t / 2 = 300 ms-1 x 7s / 2 = 1155 m.
(ii) The persistence of sound on ear drum is 1/10 of a second. The echo can be heard if the minimum distance of the source of sound from the vibrating body is 17 m. As the distance is only 10 m, ther efore, no echo is produced.
( c ) (i) Transverse vibrations are produced which are gradually damped.
(ii) A stretched string of a guitar.
(iii) As the energy of wave is dissipated its amplitude decreases.
(iv ) The body will stop vibrating.
(a) (i) A cell is sending current in an external circuit. How does the terminal voltage compare with the e.m.f. of the cell ?
(ii) What is the purpose of using a fuse in an electrical circuit ?
(iii) What are the characteristic properties of fuse wire ? 
(b) (i) Write an expression for the electrical energy spent in the flow of current through an electrical appliance in terms of I, R and t.
(ii) At what voltage is the alternating current supplied to our houses ?
(iii) How should the electric lamps in a building be connected ? 
(c) Three resistors are connected to a 6 V battery as shown in the figure given alongside :
(i) the equivalent resistance of the circuit.
(ii) total current in the circuit.
(iii) potential difference across the 7.2 W resistor.
(a) (i) Terminal voltage is slightly less than the e.m.f. of the cell.
(ii) The fuse wire melts and stops the flow of electric current in a given circuit, in case the circuit is overloaded or short circuited.
(iii) 1. Fuse wire should have low melting point around 200ºC.
2. Fuse wire should have high electrical resistance. (b)
(i) Electrical energy (E) = I2.R.t.
(ii) Alternating current is supplied at 220V for domestic consumption.
(iii) All lamps should be connected in parallel.
(c) (i) Resistance of 8Ω and 12Ω resistors in paral
(ii) Current in circuit I = V/R = 6V/12Ω = 0.5 A.
(iii) Potential difference across 7.2Ω resistor
V = I.R = 0.5 A × 7.2Ω = 3.60V
(a) (i) Write an expression for the heat energy liberated by a hot body.
(ii) Some heat is provided to a body to raise its temperature by 25ºC.
What will be the cor responding rise in temperature of the body as shown on the kelvin scale ?
(iii) What happens to the average kinetic energy of the molecules as ice melts at 0ºC ? 
(b) A piece of ice at 0ºC is heated at a constant rate and its temperature recorded at regular intervals till steam is formed at 100ºC. Draw a temperature – time graph to represent the change in phase. Label the different parts of your graph. 
( c ) 40 g of ice at 0ºC is used to bring down the temperature of a certain mass of water at 60ºC to 10ºC. Find the mass of water used.
[Specific heat capacity of water = 4200 J kg–1 ºC–1]
[Specific latent heat of fusion of ice = 336 × 103 J kg–1] 
(a) (i) Heat liberated by a body = mass × sp. heat capacity × fall in temperature= m × C × Øfall(ii) The rise in temperature on kelvin scale will be 25 K.
(iii) The average kinetic energy of the molecules remains same.
(a) The diagram alongside shows a current carrying loop or a circular coil passing through a sheet of cardboard at the points M and N. The sheet of cardboard is sprinkled uniformly with iron filings.
(i) Copy the diagram and draw an arrow on the circular coil to show the direction of current flowing through it.
(ii) Draw the pattern of arrangement of the iron filings when current is passed through the loop. 
(b) (i) Draw a simplified labelled diagram of a hot cathode ray tube.
(ii) Name a common device where a hot cathode ray tube is used. 
(c) A certain nucleus X has a mass number 14 and atomic number 6. The nucleus X changes to 7Y14 after the loss of a particle.
(i) Name the particle emitted.
(ii) Represent this change in the form of an equation.
(iii) A radioactive substance is oxidized. What change would you expect to take place in the nature of its radioactivity ? Give a reason for you answer. 
(ii) Hot cathode ray tube is used in monitors in computers.
(c) (i) The particle emitted is beta particle.
(ii) 6Y14 + b 7Y14
(iii) No change will take place in its rate of activity. It is because oxidation is a chemical change which takes at electron level. It has nothing to do with nucleus of the atom.