A 44.0 kgseal at an amusement park slides from rest down a ramp into the pool below. The top of the ramp is 1.75 m higher than the surface of the water and the ramp is inclined at an angle of 35. degrees above the horizontal.

Question

If the seal reaches the water with a speed of 4.00 {\rm m/s}, what is the work done by kinetic friction?

Answer 1

Work done AGAINST friction = (P.E loss) - (K.E. gain)

= M g H - (1/2)M V^2

(V is the speed when it hits the water)

The angle of the ramp doesn't matter when computing the answer, but it does affect how much frictional work is done

The work done BY the friction is negative