A block is released from rest at B on a smooth path of arbitrary shape. Find the speed it attains when it reaches point A.

a. (2 g h)^{0.5} b. (2 g/h)^{0.5} c. (2 g l)^{0.5} d. (2 g/l)^{0.5}

Consider the forces in the direction of motion of the block m g sin q = m a_{t} => a_{t} = g sin q but a_{t} ds = v dv => v dv = g sin q ds but dy = ds sin q The velocity of the block at A is (2 g h)^{0.5}