Question

A ray of line enter benzene from air . If the refractive index of benzene is 1.50 , by what percentage does the speed of light really reduce on entering the Benzene ?
please give me the answer for( 2 marks)

Answer 1

REFRACTIVE INDEX = 1.50

REFRACTIVE INDEX= C/V

(C - SPEED OF LIGHT IN VACUUM  , V = SPEED OF LIGHT IN MEDIUM . in this case = benzene)

1.50 = 3 x 10∧8 / speed of light in benzene

speed of light in benzene = 2 *10∧8

percentage of speed of light  reduces by ;-

(3 * 10^8 - 2* 10^8) / 3 *10^8   *   100 = 33.33%

Answer 2

Answer:

33.3 % .

Explanation:

Given :

Refractive index of benzene = 1.50

We know :

Speed of light = 3 × 10⁸ m / sec

We know formula for n :

n = speed of light in vacuum / speed of light in benzene

n = c / v

1.5 = 3 × 10⁸ / v

v = 2 × 10⁸ m / sec

Now ,

Percentage ( % ) decrease = 1  × 10⁸ / 3  × 10⁸  × 100 %

% decrease = 33.3 % .