ICSE Class 10 Question Paper 2025 Physics

PHYSICS

(SCIENCE PAPER – 1)

Maximum Marks: 80

Time allowed: Two hours

1. Answers to this Paper must be written on the paper provided separately.

2. You will not be allowed to write during first 15 minutes.

3. This time is to be spent in reading the question paper.

4. The time given at the head of this Paper is the time allowed for writing the answers.

5. Section A is compulsory. Attempt any four questions from Section B.

6. The intended marks for questions or parts of questions are given in brackets [ ].

Instruction for the Supervising Examiner

Kindly read aloud the Instructions given above to all the candidates present in the
Examination Hall.

This Paper consists of 16 printed pages.
T25 521 Turn Over
© Copyright reserved.

SECTION A (40 Marks)
(Attempt all questions from this Section.)

Question 1
Choose the correct answers to the questions from the given options. [15]
(Do not copy the questions, write the correct answers only.)

(i) A body is acted upon by two equal and opposite forces, that are NOT along the
same straight line. The body will:

(a) remain stationary

(b) have only rotational motion

(c) have only rectilinear motion

(d) have both rectilinear and rotational motion

(ii) Which among the following is a vector quantity?

(a) work

(b) power

(c) energy

(d) moment of couple

(iii) What is the correct energy transformation during burning of a candle?

(a) heat  kinetic + potential

(b) heat  chemical + light

(c) chemical  heat + light

(d) mechanical  chemical + heat

T25 521 2

(iv) When a ray of light passes from one optical medium to another, which of the
following physical quantities does NOT change?

(a) Amplitude of the wave

(b) Frequency of the wave

(c) Wavelength of the wave

(d) Speed of the wave

(v) Which one of the following combinations is the correct ascending order of
electromagnetic waves in terms of wavelength?

(a) gamma-rays, visible light, microwaves

(b) microwaves, visible light, gamma-rays

(c) gamma-rays, microwaves, visible light

(d) microwaves, gamma-rays, visible light

(vi) For a lever, a graph is plotted with load on Y-axis and effort on X-axis. Which
of the following represents the slope of the graph?

(a) Mechanical advantage

(b) Velocity ratio

(c) 1 / Velocity ratio

(d) 1 / Mechanical advantage

(vii) For a real image formed by a convex lens, the ratio of I : O = 2 : 5, then the
object is: (I is the height of the image and O is the height of the object)

(a) between O and F

(b) beyond 2F

(c) at F

(d) between F and 2F

T25 521 3 Turn Over

(viii) A ray of light is incident normally on a face of an equilateral prism. The ray gets
totally reflected at the second refracting surface. The total deviation produced
in the path of the ray is:

(a) 30°

(b) 60°

(c) 90°

(d) 120°

(ix) In a closed circuit containing a bulb and a cell, the electromotive force (𝜺𝜺) and
the terminal voltage (V) is related as.
(Given I is current and r is internal resistance.)

(a) V = 𝜀𝜀 + Ir

(b) V = 𝜀𝜀 – Ir

(c) V = 𝜀𝜀 ÷ Ir

(d) V = 𝜀𝜀 x Ir

(x) A metal piece of mass 5 g has thermal capacity 2.5 JK-1. If the mass of the metal
is tripled, then its specific heat capacity will be:

(a) 7.5 JK-1

(b) 2.5 JK-1

(c) 1.5 Jg-1K-1

(d) 0.5 Jg-1K-1

T25 521 4

(xi) Assertion (A): As the level of water in a tall measuring cylinder kept under
running tap rises, the pitch of sound gradually increases.
Reason (R): Frequency of sound is inversly proportional to the length of the
water column.

(a) Both (A) and (R) are true and (R) is correct explanation of (A).

(b) Both (A) and (R) are true and (R) is not the correct explanation of (A).

(c) (A) is true but (R) is false.

(d) (A) is false but (R) is true.

(xii) In the given circuits Y and Z, the resistors, R1 and R2, are connected in:

Y Z

(a) series in both the circuits

(b) parallel in both the circuits

(c) parallel in Y and series in Z

(d) series in Y and parallel in Z

(xiii) A radioactive element P emits one α-particle and transforms to a new element Q.
What will be the position of the element Q in the periodic table?

(a) One group to the left of P

(b) One group to the right of P

(c) Two groups to the right of P

(d) Two groups to the left of P

T25 521 5 Turn Over

(xiv) Each of the substances given below is supplied with same amount of heat.
Which one will attain the highest temperature?

Substance Lead Aluminium Copper Iron
Specific heat
capacity (cal/goC) 0.031 0.21 0.095 0.115

(a) Aluminium

(b) Copper

(c) Iron

(d) Lead

(xv) The following figure shows a small bar magnet falling freely through a copper
ring. For the observer at A, the direction of the induced current will be:

Copper ring

(a) clockwise when magnet is above and below the ring

(b) anticlockwise when magnet is above and below the ring

(c) anticlockwise when magnet is above the ring and clockwise when the
magnet is below the ring

(d) clockwise when magnet is above the ring and anticlockwise when the
magnet is below the ring

T25 521 6

Question 2

(i) Complete the following by choosing the correct answers from the bracket: [6]

(a) In uniform circular motion the centrifugal force acts __________
[towards the centre / away from the centre / along the tangential direction].

(b) Refractive index of a medium is independent of __________
[temperature / angle of incidence / wavelength of light].

(c) Heat absorbed during change of phase depends on __________ [mass /
change in temperature / specific heat capacity] of the substance.

(d) Emf of a cell is ___________ [greater than / less than / equal to] the
terminal voltage when the cell is in open circuit.

(e) In a step-up transformer the turns ratio is ___________ [more than 1 /
less than 1 / equal to 1].

(f) The nuclear radiation with lowest ionizing power is __________
[α / β / γ ].

(ii) A non-uniform kite is hanging freely from the branch of a tree as shown. Study [2]
the figure and answer the following:

Branch
of a tree

(a) Fill in the blank.
__________ (P, Q, R or S) is the most probable position of its centre of
gravity.

(b) Support your answer to (a) with a reason.

T25 521 7 Turn Over

(iii) The displacement-time graph of a sound wave produced by a vibrating wire is [2]
shown below.

(a) How will you adjust the tension in the wire, to reduce the length of PR?

(b) Which characteristic of sound is affected by the reduction in the length of
PR?

Question 3
(i) A ray of light enters a rectangular glass slab submerged in water at an angle of [2]
incidence 55°. Does this ray undergo total internal reflection when it moves
from water to glass? Justify your answer. (The critical angle for glass-water
interface is 54°.)

(ii) According to the NEW colour convention which colour of wire is connected to: [2]

(a) the metal body of the appliance

(b) the switch of the appliance?

(iii) (a) Which of the two, alternating current or direct current, produces a varying [2]
magnetic field when it flows through a conductor?

(b) State the frequency of the alternating current supply in India.

(iv) Calcuate the amount of heat absorbed by 200 g of paraffin wax to melt completely [2]
at its melting point.
[Specific latent heat of fusion of paraffin wax = 146 Jg-1]

T25 521 8

(v) Copper wire is wound around a steel bar FT. Current is allowed to pass through [2]
the coil for some time and then the bar is removed.

(a) Draw only the magnetised bar FT and mark its poles.

(b) Trace two magnetic lines of force around FT clearly indicating the
direction.

(vi) A current flows through a metallic conductor for a long period of time. State [2]
the change you would expect in its:

(a) Resistance

(b) Resistivity

(vii) Curium is a radioactive element with the symbol 247
96𝐶𝐶𝐶𝐶 named in honour of [3]
Madam Curie. The graph of number of protons vs number of neutrons for
some elements are shown below:

(a) Which point on the graph indicates the element Cm?

(b) Which point on the graph indicates daughter nucleus after Cm undergoes
radioactive decay of 1 α followed by 2 β?

(c) State the mass number of the daughter nucleus.

T25 521 9 Turn Over

SECTION B (40 Marks)
(Attempt any four questions from this Section.)

Question 4
(i) [3]

(a) Out of the three rays (I, J, H) shown in the diagram, which ray will suffer
Total Internal Reflection while inside the prism? (Critical angle of the
prism is 42o.)

(b) Copy the diagram to complete the path of the ray which you have named
in (a) till it comes out of the prism.

(ii) A rectangular glass block of refractive index 1.5 has an air bubble trapped inside [3]
it as shown in the diagram. When seen from the surface AB, it appears to be
4 cm deep.

(a) Calculate the actual depth of the air bubble from the surface AB.

(b) For which colour of light, blue or yellow, the apparent depth will be greater?

(c) Turning the glass block upside down, DOES NOT change the apparent depth
of the air bubble. State True or False.

T25 521 10

(iii) (a) An object is placed at 2F position of a convex lens. Draw a ray diagram [4]
showing the formation of the image.

(b) How will the size of the image change if we, ONLY replace the lens in the
above arrangement with another lens of a greater focal length?

Question 5

(i) An object is placed in front of a concave lens at a distance of 45 cm from it. If [3]
its image is formed at a distance of 30 cm from the lens, calculate the focal
length of the lens.

(ii) Two rays PQ and RS are incident on a rectangular glass block as shown in the [3]
diagram. Observe the diagram and answer the questions that follow.

Which of these two rays will:

(a) have greater lateral displacement on emerging out of the block?

(b) travel with greater speed in the block?

(c) scatter more in the atmosphere?

(iii) (a) Name the radiations: [4]
1. for which a quartz prism is used to study the spectrum.
2. which are used in remote sensing devices.
3. which are used in traffic signals in India.

(b) Name one property common to all electromagnetic radiations.

T25 521 11 Turn Over

Question 6

(i) Akash takes a uniform meter scale and suspends a weight of 2 N at one end 'X' [3]
and a weight of 5 N on the other end 'Y'. He then balances the ruler horizontally
on a knife edge placed at 70 cm from X. Draw a diagram of the arrangement
and calculate the weight of the ruler.

(ii) Three levers X, Y, Z of equal lengths are shown in the diagram. [3]

X

Y

Z

(a) Which class of lever do these belong to?

(b) Among these (X, Y or Z) which one will give the maximum mechanical
advantage? Justify your answer.

T25 521 12

(iii) [4]

Q
Ground

Richa weighing 40 kgf leaves point P on her skateboard and reaches point Q on
the ground with velocity 10 ms-1. Calculate:

(a) the kinetic energy of Richa at point Q.

(b) the vertical height of point P above the ground. (Use g as 10 m/s2 and
neglect friction)

(c) the kinetic energy of Richa at point R. (While moving from Q to R, she
loses 500 J of energy against friction.)

Question 7
(i) Draw a block and tackle system of pulleys with velocity ratio equal to 3. [3]

(ii) A submarine in the sea, sends ultrasonic ping and a stopwatch is started [3]
simultaneously. The stopwatch stops on receiving the reflected wave from an
obstacle and reads 1 minute 40 seconds. Calculate the distance of the obstacle
from the submarine. (Speed of sound in water 1500 ms-1.)

T25 521 13 Turn Over

(iii) The diagrams given below show two sound boxes A and B with wires of [4]
same length (l) and tension (10 kgf) but different cross-sectional areas.
Simultaneously, vibrating tuning forks of frequency 300 Hz are placed on the
boxes A and B. The paper rider falls off in case of B but not in case of A.

(a) Name and explain the phenomenon responsible for the falling off of the
paper rider in B.

(b) The wire A resonates with a tuning fork of frequency ‘f’. Is ‘f’ greater
than, less than or equal to 300 Hz? Justify your answer.

Question 8
(i) The diagram shows wiring in a meter room of a building. [3]

(a) What is the current rating of device X?

(b) What is the difference between the switch Z shown in the diagram and the
switches you use to operate different appliances at home?

(c) What is the unit of the physical quantity displayed in Y?

T25 521 14

(ii) Study the diagram given below and answer the questions that follow: [3]

3Y

(a) Name the process depicted in the diagram.

(b) What is the value of X?

(c) Identify Y, the missing product of the reaction.

(iii) [4]

Three identical bulbs B1, B2, and B3 each of power rating 18 W, 12 V are
connected to a battery of 12 V.

(a) Calculate:
1. the resistance of each bulb
2. the current drawn from the cell

(b) If the bulb B3 is removed from the circuit, then will the brightness of the
bulb B1 increase, decrease or remain the same?

T25 521 15 Turn Over

Question 9

(i) 30 g of ice at 0°C is used to bring down the temperature of a certain mass of [3]
water at 70℃ to 20℃. Find the mass of water. [Specific heat capacity of water
= 4.2 Jg-1°C-1 and specific latent heat of ice = 336 Jg-1.]

(ii) (a) A certain amount of heat will warm 1 g of material X by 10°C and 1 g of [3]
material Y by 40°C. Which material has higher specific heat capacity?

(b) Which material, X or Y, would you select to make a calorimeter?

(c) The specific heat capacity of a substance remains the same when it
changes its state from solid to liquid. State True or False.

(iii) A copper rod PQ carrying current is kept in a magnetic field as shown in the [4]
diagram.

(a) The copper rod PQ will move towards C. State True or False.

(b) Name the law used to determine the direction of motion of PQ.

(c) What will be the effect on the force experienced, if the rod PQ is replaced
by another copper rod of same length but of greater cross-sectional area?

(d) Justify your answer in (c).

T25 521 16