A block moves on a rough slope of length 10 m inclined at 30 degrees to the horizontal. The coefficiebt of friction between the block and the slope is 0.4. The block starts from rest at the top of the slope.
a) Find the speed at which the block reaches the bottom of the slope.
b) The block is then projected back up the slope with an initial speed v m/s. It just reaches the top of the slope. Find v