A Small Plane Mirror Is Rotating At A Constant Frequency Of n rotations Per Second. With What Linear Velocity (in Ms–1) Will A Light Spot Move Along A Spherical Screen Of Radius Of Curvature Of R metres If The Mirror Is At The Centre Of Curvature Of The Screen?   

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Question

A small plane mirror is rotating at a constant frequency of n rotations per second. With what linear velocity (in ms–1) will a light spot move along a spherical screen of radius of curvature of R metres if the mirror is at the centre of curvature of the screen?   

Solution

Correct option is

 

If a mirror rotates through an angle θ, the image rotates through an angle 2θ. Therefore, the linear speed of the light spot is

                     .  

SIMILAR QUESTIONS

Q1

Two transparent media A and B are separated by a plane boundary. The speed of light in medium A is  and in medium B  The critical angle for which a ray of light going from A toB is totally internally reflected is   

Q2

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Q3

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Q4

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Q5

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Q6

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Q7

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Q8

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Q9

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Q10

A ray of light incident normally on face AB of an isosceles prism travels as shown in fig. The least value of the refractive index the prism must have should be