How do you verify experimentally that the angle of refraction is more than angle of incidence when light rays travel from denser to rarer medium. (AS1)

Aim: Verify that the angle of refraction is more than angle of incidence when light rays travel from denser to rarer medium.

Procedure:

1. Take a metal disc and mark angle along its edges using protractor as shown in the figure.

2. Arrange two straws at center of disc such that they can be rotated freely about center of disc.

3. Adjust one of the straw to make the angle of 10^o and immerse half of the disc vertically into the water verify that straw is at 10^o inside the water.

4. From the top of the vessel view the straw as shown in the figure.

5. Adjust straw until both straw are in single straight line.

6. Take disc out of water and we will observe that two straws are not in straight line.

7. Measure the angle between the normal and second straw and note it.

8. Repeat for various angles and find their corresponding angle of refraction.

Observation: we will note that angle of refraction(r) is more than angle of incidence (i).

Conclusion: When the light travels from denser (water) to rarer (air) medium it bends away from the normal.