Figure shows a torch producing a straight light beam falling on a plane mirror at an angle 60^@. The reflected beam makes a spot P on the screen along y-axis. If at t=0, the mirror starts rotating about the hinge A with an angular velocity omega = 1^@per second clockwise, find the speed of the spot on screen after time t = 15 s.

Figure shows a torch producing a straight light beam falling on a plan

1.	Figure shows a torch producing a straight light beam falling on a plane mirror at an angle 60^@. The reflected beam makes a spot P on the screen along y-axis. If at t=0, the mirror starts rotating about the hinge A with an angular velocity omega = 1^@per second clockwise, find the speed of the spot on screen after time t = 15 s.
Answer» `(pi)/(15) m//s ` `(pi)/(30) m//s ` `(2pi)/(15) m//s` `(pi)/(60) m//s` Answer :C

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