online mcq test Physics For UPSC | SSC | Rail | RRB | State PSC | class 12 P21

Page 21

80132201. Which of the following is used to split white light into different colors?
A
Glass slab
B
Convex lens
C
Concave lens
D
Prism
D
80024202. Decibel is the unit used for
A
Speed of light
B
Intensity of heat
C
Intensity of sound
D
C
Correct Answer: C. Intensity of sound
80094203. The velocity of heat radiation in vacuum is
A
Equal to that of light
B
Less than that of light
C
Greater than that of light
D
Equal to that of sound
A
Correct Answer: A. Equal to that of light
80043204. In the atmosphere ultraviolet rays are absorbed by
A
Oxygen
B
Nitrogen
C
Ovone
D
Helium
C
80061205. Superconductors are those elements
A
Whose conductivity is intermediate between metals and insulators
B
Whose resistance falls almost to zero at very low temperatures
C
which turn into insulators at very low temperatures
D
which conduct electricity only at super-high temperatures
B
Correct Answer: B. Whose resistance falls almost to zero at very low temperatures
80000206. The splitting of different colors of light in a prism is
A
Reflection-of light
B
Disperson of light
C
Diffraction of light
D
Refraction of light
B
Correct Answer: B. Disperson of light
80133207. Which of the following laws validates the statement that matter can neither be created nor destroyed ?
A
Law of conservation of energy
B
Le Chatelier's Principle
C
Law of conservation of mass
D
Law of osmosis
C
Correct Answer: C. Law of conservation of mass
80017208. An electrostatic precipitator is used to control the pollution of
A
air
B
water
C
noise
D
thermal
A
80032209. Heat from the Sun reaches the Earth by
A
Reflection
B
Conduction
C
D
Convection
C
80151210. Wollen clothes keep the body warm because
A
Wool increases the temperature of the body
B