CSS Physics past papers MCQs

By: Prof. Dr. Fazal Rehman | Last updated: May 20, 2025

1. Which of the following radiations has the highest energy?
(A) Ultraviolet
(B) Infrared
(C) Gamma rays
(D) X-rays

2. A proton and an electron are placed in an electric field. Which experiences greater acceleration?
(A) Proton
(B) Electron
(C) Both equally
(D) None

3. The phenomenon of bending of light around corners is called:
(A) Reflection
(B) Refraction
(C) Interference
(D) Diffraction

4. Which principle is the basis for the working of LASER?
(A) Stimulated emission
(B) Photoelectric effect
(C) Thermionic emission
(D) Nuclear fusion

5. The energy of a photon is directly proportional to its:
(A) Wavelength
(B) Frequency
(C) Velocity
(D) Amplitude

6. A Carnot engine has an efficiency of 100% if:
(A) Sink is at 0 K
(B) Source is at 0°C
(C) Source and sink are at same temperature
(D) Sink is at 273 K

7. Which of the following is not a vector quantity?
(A) Momentum
(B) Displacement
(C) Work
(D) Force

8. The uncertainty principle was proposed by:
(A) Schrödinger
(B) Bohr
(C) Heisenberg
(D) Dirac

9. The reciprocal of focal length is known as:
(A) Power of lens
(B) Aperture
(C) Dioptre
(D) Radius of curvature