physics 20
posted by peter on .
DYNAMICS:
a skier starts at the top of a 30m hill ta an anle of 20 degrees. the skier goes straight down the firctionless slope. How long will it take the skier to get to the bottom?

The distance that he has to ski is
D = 30m/sin20 = 87.7 m
The acceleration component down the slope is g sin 20 = 3.35 m/s^2
D = (1/2)*(3.35) t^2 = 87.7 m
t^2 = 52.35 s^2
t = 7.2 seconds