Question

Kinetic Energy and Potential Energy question:

http://d.pr/i/vcK4

The gymnast descends from position B and regains contact with the trampoline when it
is in its unstretched position. At this position, her centre of mass is 3.2 m below its
position at B.

Calculate her kinetic energy at the instant she touches the unstretched trampoline

Answer 1

mass*4.2*9.8

I think

Answer 2

mass is 55

Answer 3

nope. That's PE of when the person is at B.

Answer 4

and i will be ke once the person reaches back