Physics- 2 - SSC CGL Free MCQ Test with solutions

Pressure is correctly defined as force per unit area (P = F/A). However, atmospheric pressure decreases with increasing altitude due to the thinning of air, making Statement 2 incorrect.

At the highest point, the ball’s velocity is zero as it momentarily stops. However, acceleration due to gravity (9.8 m/s² downwards) remains constant throughout the motion.

Potential energy is stored energy due to position or configuration. A stretched spring stores elastic potential energy. The other options represent kinetic energy due to motion.

Archimedes’ Principle states that the buoyant force on an object immersed in a fluid is equal to the weight of the fluid displaced by the object.

Liquids generally expand more than solids for the same temperature increase due to weaker intermolecular forces. Gases also expand significantly with temperature, making Statement 2 incorrect.

Power is the rate of doing work, measured in watts, where 1 watt = 1 joule per second. Newton-meter is work (joule), and the others are not equivalent.

Electromagnetic waves (e.g., light, radio waves) can travel through a vacuum, unlike sound, water, or seismic waves, which require a medium.

The power of a lens is given by P = 1/f, where f is the focal length in meters. For f = 20 cm = 0.2 m, P = 1/0.2 = 5 dioptres (D).

Ohm’s Law (V = IR) states that current (I) is directly proportional to voltage (V) and inversely proportional to resistance (R) in ohmic conductors. It does not apply to non-ohmic conductors, making Statement 2 incorrect.

Capillarity, the rise or fall of liquid in a narrow tube, is caused by surface tension, which results from cohesive and adhesive forces of the liquid.

Transformers work on the principle of mutual induction, where a changing magnetic field in one coil induces an EMF in another coil, allowing voltage to be stepped up or down.

Specific latent heat of fusion is the heat required to change 1 kg of a substance from solid to liquid at its melting point without a change in temperature.

A plane mirror always forms a virtual, erect image of the same size. A concave mirror can form real images (e.g., object beyond focal point) or virtual images (e.g., object between mirror and focal point).

The SI unit of force is the newton (N), defined as kg·m/s². Joule is for energy, watt for power, and pascal for pressure.

The Doppler effect, the change in frequency of a wave due to relative motion, is used in radar to measure the speed of moving objects like cars. SONAR uses sound reflection, not the Doppler effect.

Beta decay involves the emission of an electron (beta particle) from the nucleus when a neutron transforms into a proton.

Efficiency is the ratio of useful work output to the total work input, expressed as a percentage, accounting for energy losses (e.g., due to friction).

The first law of thermodynamics is the conservation of energy (energy cannot be created or destroyed). The second law states that heat cannot spontaneously flow from a colder to a hotter body without external work, supporting the concept of entropy.

Myopia (nearsightedness) is the eye defect where distant objects appear blurred due to the image forming in front of the retina, corrected by a concave lens.

A diode is a semiconductor device that allows current to flow in one direction. Transformers, capacitors, and fuses are not semiconductors.