Question

If the absolute refractive indices of water and glass are 4/3 and 3/2 respectively,then what is the ratio of speed of light in water to that in glass?

Options :

• 2
• 8/9
• 9/8
• 1/2
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Answer 1

Answer : Option 3 is correct.

Explanation :

• Let the refractive index, speed of light in vaccum and speed of light in a substance be n, c and v, respectively.

• The relation between between refractive index and speed of light in any substance is given by

n = c/v

• So, v = c/n

• Hence, Speed of light in water = 3c/4

and Speed of light in glass = 2c/3.

• Ratio of speed of light in water to glass = (3c/4)/ (2c/3)

= 9/8.

Answer 2

guys iska answer kya hai ???