A Plane Mirror Which Rotates 104 times Per Minute Reflects Light On To A Stationary Mirror 50 m away. This Mirror Reflects The Light Normally So That It Strikes The Rotating Mirror Again. The Image Observed In The Rotating Mirror Is Shifted Through 2.4 Minutes From The Position It Occupies. When The Rotating Mirror Is Stationary, What Is The Speed Of Light? 

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Question

A plane mirror which rotates 104 times per minute reflects light on to a stationary mirror 50 m away. This mirror reflects the light normally so that it strikes the rotating mirror again. The image observed in the rotating mirror is shifted through 2.4 minutes from the position it occupies. When the rotating mirror is stationary, what is the speed of light? 

Solution

Correct option is

 

When the plane mirror is rotated through θ, the image formed by the mirror is rotated through 2θ.

Here                  

                       

                      

Here,

                       

                              

                    

But t = time taken by light to go from M1 to M2 and returned back

                      

From Eqs. (i) and (ii)  

                       

SIMILAR QUESTIONS

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