Light, Heat, Thermodynamics, Wave Motion, Sound, Optics & Oscillations - Category Wise Question And Answer Practice Test With Solutions

Question : 16 [UPPCS (Mains) 2003]

Direct viewing of Sun during total solar eclipse causes irreversible damage to eyes. The retinal burn is caused by which one of the following components of the Sun rays?

a) Ultra-violet light

b) Rainbow light

c) Heat

d) Infra-red light

Question : 17 [NDA]

A Centigrade thermometer and Fahrenheit thermometer are dipped in boiling water. The temperature of water is lowered till the Fahrenheit thermometer registers half of its upper fixed point. What is the corresponding fall temperature registered by the Centrigrade thermometer?

a) Approximately 41°C

b) Half of its range of temperature between the upper and the lower fixed points

c) Approximately 59°C

d) 18°C

Question : 18 [RAS/RTS (Pre) 1999]

Find out the odd colour from the following options.

a) Red

b) Brown

c) Green

d) Yellow

Question : 19 [PSC (Pre) 2017]

In fibre optics communication, the signal travels in the form of

a) Micro wave

b) Radio wave

c) Light wave

d) Electric wave

Question : 20

Power of accommodation of eye implies

a) change of focal length of eye lens

b) control intensity

c) prevent internal reflection of light

d) All of the above