Physics
The diagram given below shows a ski jump. A skier weighing 60kgf stands at A at the top of ski jump. He moves from A and takes off for his jump at B.
(a) Calculate the change in the gravitational potential energy of the skier between A and B.
(b) If 75% of the energy in part (a) becomes the kinetic energy at B, calculate the speed at which the skier arrives at B.
(Take g = 10 ms-2).
(c) Does total mechanical energy change during the ski jump?
Related Questions
A metal ball of mass 2kg is allowed to fall freely from rest from a height of 5m above the ground.
- Taking g = 10ms-1, calculate:
- the potential energy possessed by the ball when it is initially at rest.
- the kinetic energy of the ball just before it hits the ground?
- What happens to the mechanical energy after the ball hits the ground and comes to rest?
- Taking g = 10ms-1, calculate:
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(Take g = 10 m s-2).