1. . The mode of transfer of heat from layer to layer without any visible motion of particles is called:
(A) Transmission
(B) Convection
(C) Radiation
(D) Conduction
2. . X–rays are similar in nature to:
(A) Cathode rays
(B) Gamma rays
(C) Positive rays
(D) Alpha rays
3. . Photoelectric effect occurs only when light used exceeds a certain:
(A) Frequency
(B) Wavelength
(C) Velocity
(D) Intensity
4. . Number of modes of transfer of heat are:
(A) 2
(B) 3
(C) 4
(D) Infinite
5. . Transfer of heat from one part to another part by actual movement of particles is known as:
(A) Radiation
(B) Conduction
(C) Convection
(D) None of these
6. . According to Stefan-Boltzmann law:
(A) E ∝ T⁴
(B) E ∝ T³
(C) E ∝ T²
(D) E ∝ T
7. . Velocity of X–rays is equal to that of:
(A) γ–rays
(B) α–rays
(C) Sound
(D) None of these