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 nature of radiations emitted by a hot body depends upon its:	A. Metarial B. Temperature C. colour D. Volume
2	Position and momentum of a particle cannot both be measured simultaneously with perfect accuracy. This is the statement of	A. photoelectric effect B. pair production C. Compton effect D. uncertainty principle
3	When platinum wire is heated, it appears cherry red at	A. 1600°C B. 900°C C. 1100°C D. 1300°C
4	If a material object moves with the speed of light 'C' its mass becomes	A. Equal to its rest mass B. Four times of its rest mass C. Double of its rest mass D. Infinite
5	When low energy photon interact with a metal,which of the following effect is likely to be taken place	A. pair production B. photoelectric C. Compton effect D. None of these
6	The unit of work function is:	A. Joule B. Electron volt C. That of threshold frequency D. Both (A) and (B)
7	When platinum wire is heated, then at the temperature of 500 ^oC, it becomes:	A. Yellow B. Orange red C. Dull red D. White
8	The mass 'm' of a body moving at 0.8 c (whose rest mass is mo) becomes	A. 2 mo B. 1.67 mo C. 0.67 mo D. 2.67 mo
9	Compton shift refers to:	A. Photon B. Meson C. Proton D. Positron
10	Which one of the following physical quantities changes with relativistic speed	A. Length B. Mass C. Time D. All of the above