CBSE-XI-Physics
21: Speed of Light
- #1Light passes through a closed cylindrical tube containing a gas. If the gas is gradually pumped out, the speed of light inside the tube will
(a) increase
(b) decrease
(c) remain constant
(d) first increase and then decreasedigAnsr: aAns :
(a) increase
If the gas is gradually pumped out, a vacuum will be created inside the closed cylindrical tube, and experimentally, light travels at the fastest speed in vacuum as compared to any other medium.
Page No 448: