A skier is gliding along at 3.0m/s on horizontal, frictionless snow. He suddenly starts down a incline. His speed at the bottom is 15m/s.
a) what is the length of the incline?
b) how long does it take to reach to bottom?

Question

A skier is gliding along at 3.0m/s on horizontal, frictionless snow. He suddenly starts down a incline. His speed at the bottom is 15m/s.
a) what is the length of the incline?
b) how long does it take to reach to bottom?

anonymous · Answer

There's a 10 degree incline

jamesj · Answer

So we're assuming friction is zero.  The change in kinetic energy has to come from somewhere.  It comes from gravitational potential energy.  

Use that fact to calculate the vertical distance he must have gone down.  

Then use elementary trigonometry to find the length of that incline, being the hypothenuse of right-angled triangle with angle 10 degrees.

jamesj · Answer

Make sense?

anonymous · Answer

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as total energy re,mains conserves
x ia lenghth of slope