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General
Easy
Question
A flat mirror M is arranged parallel to a wall W at a distance l from it. The light produced by a point source S kept on the wall is reflected by the mirror and produces a light spot on the wall. The mirror moves with velocity v towards the wall
- The spot of light will move with the speed v on the wall
- The spot of light will not move on the wall
- As the mirror comes closer the spot of light will become larger and shift away from the wall with speed larger then v
- The size of the light spot on the wall remains the same
The correct answer is: The spot of light will not move on the wall
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