ECAT Pre Engineering Physics Chapter 19 MCQ Test With Answer

Top Scorers Of Physics ECAT Pre Engineering Chapter 19 Dawn of Modern Physics MCQ`s Test

Sr.#	Question	Answer
1	Electromagnetic -radiation means:	A. Photons B. protons C. Electrons D. Mesons
2	A non-inertial frame of reference is one, in which	A. law of inertial is valid B. all laws of physics are the same in all frames C. a>0 or a<0 D. a=0
3	A black body is	A. an ideal absorber B. an ideal radiator C. both of them D. none of them
4	Electromagnetic radiation or photons interact with matter in	A. two distinct ways B. three distinct ways C. four distinct ways D. five distinct ways
5	The energy of photon 'E' is proported to	A. The magnetic field H B. The electric field E C. Both the electric and magnetic field H and E D. Frequency
6	At the temperature, a body emits radiation which is principally	A. of long wavelengths in the visible region B. of long wavelengths in the invisible infrared region C. of short wavelength in invisible ultraviolet region D. none of these
7	Wien's constant is measured in:	A. Metre per kelviin B. Metre kelvin C. Kelvin per meter D. Joules
8	The value of threshold frequency for different metals is	A. different B. same C. may be different or may be same D. none of these
9	If A represents linear momentum and c, the velocity of light, then unit of pc in international system of units is:	A. Newton B. Joule C. Joule-Sec D. Joule-s^-1
10	The photon of radio-waves has energy of about	A. 1 Me V B. 1 Ke v C. 10^-10e v D. 10¹⁰e v