Previous Year Questions General Science for CDS & AFCAT: 4th January

Previous year questions must be prepared when it comes to the preparation of CDS & CAPF examinations. Defenceadda is providing you with the previous year questions of General Science Section.

Q1.  If an object having mass of 1 kg is subjected to a force of 1 N it moves with
(a) A speed of 1 m/s
(b) A speed of 1 km/s
(c) An acceleration of 10 metre per second sq.
(d) An acceleration of 1 metre per second sq.

Q2. An athlete diving off a high springboard can perform a variety of exercises in the air before entering the water below. Which one of the following parameters will remain constant during the fall?
(a) The athlete’s linear momentum
(b) The athlete’s moment of inertia
(c) The athlete’s kinetic energy
(d) The athlete’s angular momentum

Q3. The pressure exerted on the ground by a man is greatest
(a) When the lies down in the ground
(b) When the stands on the toes of one foot
(c) When the stands with both foot flat on the ground
(d) All of the above yield the same pressure

Q4. A passenger in a moving train tosses a five rupee coin. If the coin falls behind him, then the train must be moving with a uniform
(a) Acceleration
(b) Deceleration
(c) Speed
(d) Velocity

Q5. As the sunlight passes through the atmosphere, the rays are scattered by tiny particles of dust, pollen, soot and other minute particulate matters present there. However, when we look up, the sky appears blue during mid-day because
(a) Blue light is scattered most
(b) Blue light is absorbed most
(c) Blue light is reflected most
(d) Ultraviolet and yellow component of sunlight combine

Q6. The force acting on a particle executing simple harmonic motion is
(a) Directly proportional to the displacement and is directed away from the mean position
(b) Inversely proportional to the displacement and is directed towards the mean position
(c) Directly proportional to the displacement and is directed towards the mean position
(d) Inversely proportional to the displacement and is directed away from the mean position

Q7. Which one of the following statements is correct?
(a) The angle of contact of water with glass is acute while that of mercury with glass is obtuse
(b) The angle of contact of water with glass is obtuse, while that of mercury with glass is acute
(c) Both the angle of contact of water with glass and that of mercury with glass are acute
(d) None of the above

Q8. Why are inner lining of hot water geysers made up of copper?
(a) Copper has low heat capacity
(b) Copper has high electrical conductivity
(c) Copper does not react with steam
(d) Copper is good conductor of both heat and electricity

Q9. Half portion of a rectangular piece of ice is wrapped with a white piece of cloth while the other half with a black one. In this context, which one among the following statements is correct?
(a) Ice melts more easily under black wrap
(b) Ice melts more easily under white wrap
(c) No ice melts at all under the black wrap
(d) No ice melts at all under the white wrap

Q10. The blackboard seems black because it
(a) Reflects every color
(b) Does not reflect any color
(c) Absorbs black color
(d) Reflects black color

SOLUTIONS
S1. Ans.(d)
Sol. As we know, F = ma

S2. Ans.(d)
Sol. When a athlete jumps from the spring board, he curls his body by rolling his arms and legs in. By doing so, he decreases moment of inertia of his body and hence angular speed increases to conserve the angular momentum.

S3. Ans.(b)
Sol. Pressure is normal force per unit area, therefore, for lesser value of area pressure is greatest.

S4. Ans.(a)
Sol. As the passenger tosses the coin, it goes up and is in motion with the initial speed of the train but if the train is accelerated, so its speed increases. But the coin is in the air with initial speed of train, so the train slightly moves forward from the coin with the person and coin falls behind him. It happens when train is moving with accelerated motion.

S5. Ans.(a)
Sol. Since, wavelength of blue colour is least among three primary colours red, green and blue, so violet colour scattered most. The scattered light in the sky contains blue colour in plenty and therefore sky appears blue.

S6. Ans.(c)
Sol. The restoring force acting on the particle is always proportional to the displacement of the particle from the equilibrium position and is always directed towards the equilibrium position.

S7. Ans.(a)
Sol. For ordinary water and glass it is about 8° (acute angle) and for mercury and glass it is about 135° (obtuse angle).

S8. Ans.(d)
Sol. Copper is a good conductor of both heats electricity due to this it is used in all such appliance where quick heat transfer is required.

S9. Ans.(a)
Sol. Ice under black wrap will melt easily because dark colour (black) absorbs the most of light energy falling on it.

S10. Ans.(b)
Sol. Blackboard absorbs all the colours of light falling on it and does not reflect any colour due to which it appears black.