Q.24

Expert-verified
Found in: Page 452

### Physics for Scientists and Engineers: A Strategic Approach with Modern Physics

Book edition 4th
Author(s) Randall D. Knight
Pages 1240 pages
ISBN 9780133942651

# How long does it take light to travel through a 3.0-mm thick piece of window glass?Through what thickness of water could light travel in the same amount of time?

Part (a) The time taken by the light to travel through a 3.0-mm thick piece of window glass is .

Part (b) The thickness of water through which the light travels in the same amount of time is 3.38 mm.

See the step by step solution

## Part (a) Step 1. Given information:

The thickness of window glass is

The speed of light in vacuum is

The refractive index of glass is n = 1.5

The refractive index of water is

## Part (a) Step 2. Calculating the time taken to travel through the glass window:

The formula to calculate the speed of light in glass window is given by

Substitute for c and 1.5 for n into the above formula to calculate the speed.

The rate of change of distance with respect to time is defined as the speed.

The formula to calculate the time taken is given by

Substitute for d and for v into the above formula to calculate the time taken.

## Part (b) Step 1. Calculating the thickness of water :

The speed of light travelling in water is given by

Substitute and 1.33 for into the above formula to calculate the speed.

The formula to calculate the thickness of water can the light travel is given by

Substitute into the above formula to calculate the thickness.