Question

The speed of light in air is 3x10*8m/s if the refractive indices of glass is 1.5.find the time taken by light to travel a distance of 10cm in glass (s=d/t)

Answer 1

Refractive index = c/v

1.5 = 3×10^8/v

v= 2×10^8 m/s.

Now, The time has been asked.

We have, distance= 10cm or 0.1m

And, speed = 2×10^8

So, time taken = d/s

=0.1/2×10^8

= 5× 10^(-10)

Hope it helps...❤️❤️

Answer 2

Answer:

Given:

Speed of light in air (c)=3×10^8m/s

Refractive indices of glass (μ)=1.5

Distance travelled by light (d)=10cm=10/100m=0.1m

Time taken by light (t) = ?

Solution:

Speed of light in glass (v) = distance/ time

v=0.1/t

Refractive index (μ)  = Speed of light in vacuum(c)/speed of light in glass(v)

1.5 = 3x10^8/0.1/t

1.5 = 3x10^8 × t/0.1

t = 1.5 × 0.1/3x10^8

t = 5×10^(-10) sec.

Therefore, the time taken by light to travel a distance of 10cm in glass is 5×10^(-10) sec.