Consider the situation shown in figure. The elevator is going up with an acceleration of 2.00 m/s2 and the focal length of the mirror is 12.0 cm. All the surfaces are smooth and the pulley is light. The mass – pulley system is released from rest (with respect to the elevator ) at t = 0 when the distance of B from the mirror is 42.0 cm. find the distance between the image of the block B and the mirror at t = 0.200 s. Take g = 10 m/s2



Correct option is

v = 8.57 cm


mg + 2m – T = ma

T = ma   

Solving a = 6 m/s2

          u = 1 – (42 – 12) = 1 – 30 cm,   f = + 12 cm




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