A 72.0 kg skateboarder wants to just make it to the upper edge of a "quarter pipe", a track that is one-quarter of a circle with a radius of 4.65 m. What speed (in m/s) does he need at the bottom assuming that the local acceleration due to gravity is 9.80 m/s2?

Answer 1

The KE at the bottom (where the velocity is a maximum value V, must equal the PE increase at the top, where the velocity is 0. .

(1/2)MV^2 = M g R

V = sqrt (2 g R) = 9.55 m/s