Question

Describe an experiment to verify laws of reflection.

Answer 1

Laws of reflection are,

1. The angle of incidence and the angle of reflection are equal i.e. $\angle i=\angle r$.
2. The incident ray, the reflected ray, and the normal lie in the same plane.

Experiment-

1. First, take a wooden board, then fix a white paper on it.
2. Draw a straight line in the middle of the paper and mark it as $LL\text{'}$
3. Then draw a perpendicular to $LL\text{'}$ and name it as $PP\text{'}$
4. Now, place a mirror $YY\text{'}$on the line $LL\text{'}$in a way that the polished side of the mirror is along the line.
5. Fix two pins $AandB$ on the line $QP\text{'}$ at least $10cm$ apart.
6. Look in the mirror to find the images of pins $AandB$ , two images $A\text{'}andB\text{'}$ will be shown, fix pins there also.
7. Join the points $A\text{'}andB\text{'}$ and a straight line $P\text{'}R$ will be formed.
8. Remove all the pins and mark the points with pen or pencil.
9. Measure the $\angle QP\text{'}P=\angle iand\angle PP\text{'}R=\angle r$ . It is found that $\angle i=\angle r$ . Hence, proving the first law of reflection true.
10. Also, the incident ray reflected ray and the normal lie in the plane of the paper, so, they lie in the same plane, Hence, proving the second law of reflection true.