what is the experimental verification of the laws of reflection
Answers
Answer:
1)Fix the white paper on the thermocol sheet with the help of pins.
2)Place the mirror near to one edge of the paper and mark its position.
3)Place two pins vertically on one side of the normal so that line joining two pins make an angle of approximately 30 degree with the normal.
4)See image of two pins from other side of the normal and place a pin vertically so that it is in line with images of other two pins. Similarly, place one more pin at some distance from this pin.
5)Extend the lines. Measure angle of incidence and angle of reflection.
6)Repeat for two more incident angles (say 45 degree and 60 degree).
7)Now, see the head of the pins in step (3). Raise one of the pin and press another pin.
8) Now repeat step (4) such that images of the pin-head are aligned.
9) Visualise the plane containing incident ray, reflected ray and normal. You may place a paper on this plane. 10)Raise another pin and visualize again.
Laws of reflection :-
(i) The incident ray, the reflected ray and the normal at the point of incidence, lie in the same plane.
(ii) The angle of Incidence and angle of reflection are equal I.e. ∠i=∠r.
Verification:-
Take a wooden drawing board and fix a white sheet of paper on it. In the middle of paper draw a straight line KK\ Mark a point B on it. Draw a perpendicular BN. Place a mirror XX' on line KK' such that the polished side of the mirror is along the line. Hold the mirror in the mirror holder.
Fix two steel pins P and Q on the straight line AB at least 10 cm apart. Look for the images of the pins P and Q and fix two pins P a such that P', Q', and images of P and Q are all in the same straight line. Remove the pins and draw small circles around the pinpricks.
Remove the mirror also. Join P'Q' and produce the straight line to meet at B. Measure ∠ABN = i and ∠CBN = r.
It is found that ∠i=∠r.
This proves that the Angle of Incidence is equal to the Angle of Reflection.
As the incident ray, the reflected ray and the normal lie in the plane of the paper, therefore, they lie in the same plane.
