ECAT Pre Computer Science Chapter 19 MCQ Test With Answer

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

Sr.#	Question	Answer
1	The general theory of relativity treats problems involving	A. inertial frame of references B. accelerating frame of references C. both of these D. none of these
2	When a platinum wire is heated, it appears dull red at about	A. 500°C B. 900°C C. 1100°C D. 1300°C
3	When a position comes close to an electron they annihilate into photons such that	A. each photon has energy 0.51 Me v B. each photon has energy 1.02 Me v C. each photon has energy 0.25 Me v D. none of these
4	The inside cavity of the black body is	A. painted white B. painted silver C. blackened with soot D. painted red
5	The special theory of relativity treats problems invoving	A. inertial frame of references B. accelerating frame of references C. both of these D. none of these
6	The Einstein's changes in length, mass and time are not observed in common life because	A. We dont observer then seriously B. The masses are too large C. Their speed is too small than the speed of right D. All of the above
7	A black body is	A. an ideal absorber B. an ideal radiator C. both of them D. none of them
8	Photoelectric effect takes place with a photon of:	A. Very high energy B. Very low energy C. Low energy D. High energy
9	0.1 kg mass will be equivalent to the energy	A. 9 x 10¹⁵J B. 5 x 10⁸J C. 6 x 10¹⁶J D. 9 x 10^-16J
10	The mass of an object will be doubled at speed	A. 1.6 x 10⁸ms^-1 B. 2.6 X 10⁸ms^-1 C. 2.6 x 10⁷ms^-1 D. 2.6 x 10⁹ms^-1