Problem 65.

A skier is accelerating down a 30 degree hill at .

(a) What is the vertical component of her acceleration?

(b) How long will it take her to reach the bottom of the hill, assuming she starts from rest and accelerates uniformly, if the elevation is 300 m?

Solution:

(a) If we assume that the direction of the vertical axis is downward then the vertical component is positive and is equal to

(b) This is the motion with constant acceleration then the equation which describe this motion is the following:

The traveled distance (L) is related to the elevation (h) by the equation:

Now we know acceleration and the traveled distance then we can find the traveled time: