ICSE Specimen Class 10 Physics Sample Paper 2025 Solutions
ICSE Board Class 10 Physics Sample Paper 2025 Solutions is available with Explanation. New Sample Paper Solutions ICSE Board 2025 Physics all Question Answers by Expert Teachers.
Section A
(i) A moment of couple has a tendency to rotate the body in an anticlockwise direction. Then the moment of couple is taken as:
(a) positive
(b) negative
(c) maximum
(d) zero
Answer: positive.
Explanation: The pair of forces formed by the external force and the force of reaction is called a couple. Two forces together form a couple rotates in anticlockwise direction.
We know from moment of force that, If the effect on the body is to turn it anticlockwise, the moment of force is called anticlockwise moment and it is taken positive.
(ii) The kinetic energy of a given body depends on the:
(a) position
(b) centre of gravity of the body.
(c) momentum
(d) displacement
Answer: (c) momentum
Explanation: The energy possessed by a body due to its state of motion is called its kinetic energy. The kinetic energy of a given body depends on the momentum (product of mass and velocity of the object).
Kinetic energy = 1/2 mv^2
(iii) For burning of coal in a thermoelectric station, the energy conversion taking place is:
(a) chemical to heat to mechanical
(b) chemical to heat to mechanical to electrical
(c) chemical to heat to light
(d) heat to chemical to mechanical
Answer: (b) chemical to heat to mechanical to electrical
Explanation: The energy possessed by the fossil fuels (i.e. coal) is known as chemical energy, When chemicals is burning (such as coal) it will produce heat energy.
In a thermoelectric station, This heat energy forms a steam. In a steam turbine heat energy is used to obtain work (i.e. mechanical energy). Then the turbine runs the electric generators that convert mechanical energy to electrical energy.
(iv) The adjacent diagram shows the movable block of a block and tackle system with effort in a convenient direction. From the diagram we can conclude that the number of pulleys used in the fixed block are
(a) 1
(b) 3
(c) 2
(d) 4
Answer: (c) 2
Explanation: In block and tackle system, two blocks of pulleys are used. One block at upper having sevaral pulley attatched to the rigid support (i.e. fixed) and the other block at lower having sevaral pulley is movable. For the convenience of applying effort in downward direction, the number of pulleys in the movable lower block is kept either equal to or one less than the number of pulleys in the fixed upper block. From the diagram we can conclude that the number of pulleys used in the fixed block are 2.
(v) White light is dispersed by a prism. Inside the prism, compared to the blue light, the red light
(a) slows down less and refracts more
(b) slows down more and refracts less
(c) slows down more and refracts more
(d) slows down less and refracts less
Answer: (d) slows down less and refracts less
Explanation: The refractive index of a given transparent medium is different for the light of different colours. It decreases with the increase in the wavelength of light. Thus for visible light the refractive index of the material of a prism is greater in blue then red colour. Consequently a given prism deviates blue light the most then the red light.
(vi) An endoscope uses optic fiber to transmit high resolution images of internal organs without loss of information. The principle of light that is used by the optic fiber is based on:
(a) refraction
(b) reflection
(c) scattering
(d) total internal reflection.
Answer: (d) total internal reflection.
Explanation: In the process of total internal reflection 100% energy of light is reflected back. No other device produces 100% reflection due to absorption and refraction of some part of light. Due to this property The principle of light that is used by the optic fiber is total internal reflection.
(vii) A convex lens has focal length 12 cm with an object at a distance of 20 cm in front of the lens. He obtains a blurred image on the screen placed at a distance of 23 cm in front of the lens. In order to obtain the clear image, he has to move the screen
(a) towards the lens.
(b) away from the lens.
(c) to a position very far away from the lens.
(d) either towards or away from the lens.
Answer: (b) away from the lens.
Explanation:
Here value of F in front of the length is 12 cm
Therefore 2F is 12 x 2 = 24 cm.
Here object is placed at a distance of 20 cm in front of the lens. That means the object is placed between F (12 cm) and 2F (24 cm).
We know that, when object is placed between F and 2F then the image is formed beyond 2F (beyond the lens), real and inverted.
Here in question, screen is placed at a distance of 23 cm, that means betwwen F (12 cm) and 2F (24 cm) beyond the lens.
So, He obtains a blurred image. this is because the image is formed beyond 2F.
Thats why, In order to obtain the clear image, he has to move the screen away from the lens.
(viii) Assertion(A): Infrared radiations travel long distance through a dense fog and mist.
Reason(R): Infrared radiations undergo minimal scattering in earth’s atmosphere.
(a) both A and R are true and R is the correct explanation of A.
(b) both A and R are True and R is not the correct explanation of A.
(c) assertion is false but reason is true.
(d) assertion is true but reason is false.
Answer: (a) both A and R are true and R is the correct explanation of A.
Explanation: Infrared radiations are scattered less by the earths atmosphere because of their long wavelength (since intensity of scattered radiation 1/λ^4). Hence they can penetrate deep inside the atmosphere even in fog.
(ix) Two sound waves X and Y have the same amplitude and the same wave pattern but their frequencies are 60 Hz and 120 Hz respectively, then
(a) X will be shriller and Y will be grave
(b) X will be grave and Y will be shriller
(c) X will differ in quality than Y
(d) X is louder than Y.
Answer: (b) X will be grave and Y will be shriller
Explanation: We know that, greater the frequency shriller the sound produced. Thats why sound waves X having 60 hz will produce grave (flat) sound and 2nd one Y (120 hz) will produce shriller sound.
(x) The graph of voltage vs current for four different materials is shown below.
Which of these four materials would be used for making filament of a bulb?
(a) Q
(b) S
(c) P
(d) R
Answer: (c) P
Explanation: The material p (tungsten) will be used for making filament of a bulb because,
We know that, the R = V/I [where R = resistance, V = voltage and I = current]
From the I-V graph we can see that for the same amount of voltage the current in the material P is lower than the others. which means that the resistivity of the material P is higher than the others. So a material with higher resistance will be suitable for making a filament of a bulb as it will produce more light than the other elements.
(xi) According to the old convention, the colour of the earth wire is:
(a) black
(b) green
(c) yellow
(d) red
Ans. (b) green
Explanation: According to the old convention, the colour of the earth wire is green. The colour coding of wires helps us to connect the switch, fuse, socket etc. through proper wire in the circuit of the house wiring.
(xii) Current is flowing through a coil as shown in the figure. Which one of the given figures will correctly depict the magnetic polarity and the direction of the lines of force along the axis of the coil.
Answer: C
Explanation: Here, current is flowing in clockwise direction in the figure in a circular loop that means south pole is observed.
On the above options only No. A and No. C showing south pole. Out of this option c is correct which showing properly that current is flowing through the coil.
(xiii) Heat capacity of a body is the:
(a) energy needed to melt a body without change in its temperature.
(b) energy needed to raise the temperature of a body by 1°C
(c) increase in volume of the body when its temperature increases by 1°C
(d) total amount of internal energy that is constant.
Answer: (b) energy needed to raise the temperature of a body by 1°C
Explanation: Heat capacity is the amount of heat energy required to raise the temperature of entire body by 1 degree celsisus.
(xiv) The amount of heat energy required to melt a given mass of a substance at its melting point without any rise in its temperature is called as the:
(a) specific heat capacity
(b) specific latent heat of fusion
(c) latent heat of fusion
(d) specific latent heat of freezing
Answer: (c) latent heat of fusion
Explanation: The heat energy absorbed or liberated in change of phase is not externally manifested by any rise or fall in temperature, it is called the latent heat.
(xv) A nucleus of an atom consists of 146 neutrons and 95 protons. It decays after emitting an alpha particle. How many protons and neutrons are left in the nucleus after an alpha emission?
(a) protons 93, neutrons = 142
(b) protons 95, neutrons 144
(c) protons 93, neutrons = 144
(d) protons= 95, neutrons = 142
Answer: (c) protons 93, neutrons = 144
Explanation: If an unstable nucleus contains much more neutrons than the number of protons, it may emit a particle containing two protons and two neutrons tightly bound together, known as alpha particle. If the nucleus X os a radioactive element of mass number A and atomic number Z emits an alpha particle, the daughter nucleus Y of a new element is formed which has mass number equal to (A – 4) and atomic number equal to (z – 2). Thus due to emission of alpha particle, atomic number Z decreases by 2 units (146 neutrons – 2 = 144 neutrons & 95 protons – 2 = 93 protons).
Section B
Note: All the answers of Section B with details diagram will shortly upload in this page.