Asked by Mika
A skier is accelerating down a 30.0 degrees hill at 1.80m/s^2.
How long will it take her to reach the bottom of the hill, assuming she starts from rest and accelerates uniformly, if the elevation change is 375 m?
Apparently the answer isn't 20.4 s...
Can someone help me please?
How long will it take her to reach the bottom of the hill, assuming she starts from rest and accelerates uniformly, if the elevation change is 375 m?
Apparently the answer isn't 20.4 s...
Can someone help me please?
Answers
Answered by
drwls
The distance traveled to reach the bottom is 375/sin30 = 750 m
To travel Z = 750 m while accelerating uniformly in that direction at a = 1.80 m/s^2, the time T needs to satisfy the equation
(a/2)*T^2 = 750
T^2 = 750/0.9
T = 28.9 s
To get 20.4 s, you confused the elevation change with the distance traveled.
To travel Z = 750 m while accelerating uniformly in that direction at a = 1.80 m/s^2, the time T needs to satisfy the equation
(a/2)*T^2 = 750
T^2 = 750/0.9
T = 28.9 s
To get 20.4 s, you confused the elevation change with the distance traveled.