To Verify The Law Of Rotation Of Light.

NAME OF THE EXPERIMENT: TO VERIFY THE LAW OF ROTATION OF LIGHT. 

APPARATUS REQUIRED:

• Plane mirror
• Protector
• Measuring scale
• A4 size paper
• Fixing & Hair Pins
• Cardboard or Drawing board

THEORY:

Law of rotation states that "When the mirror rotates through an angle θ, then the reflected ray rotates through angle 2θ"

PROCESS:

• A4 size paper was fixed on the Cardboard with the help of pins.
• A straight line 'PQ' was drawn through middle of paper.
• Some straight lines were drawn 0M¹, OM²,..., etc. at point 'O' making angle of 10, 20,..., etc. with st line 'PQ'
• An incident ray IO was drawn So that ∠IOM was 40°, two pins about 10cm apart fixed on IO
• The plane mirror was placed vertically such that its reflecting surface coincides with 'PQ'
• Looking along OR¹ two other pins were fixed along OR so that reflected images of the first two pins appear
  to be in the same st. line as the third and fourth pins. The distance between pins should always be more
  than 10 cm
• Then the mirror was placed in positions OM¹, OM², OM³, etc. were obtained.
• The angles between OR and OR¹, OR and OR² etc were measured.

OBSERVATION:

Angel of rotation of		Inference - ROR'
mirror ie. ∠MOM' θ	reflected ray ie. ∠ROR' 2θ
10	20	β = 2θ
20	40
30	60
40	80
50	100

CONCLUSION:

Reflected ray was rotated through 2θ when mirror was rotated through θ.
When the mirror rotates through an angle θ, then the reflected ray rotates through angle 2θ