posted by Kayla .
A skateboarder, starting from rest, rolls down a 12.5-m ramp. When she arrives at the bottom of the ramp her speed is 6.45 m/s.
(a) Determine the magnitude of her acceleration, assumed to be constant.
V = sqrt(2 a X) applies when the starting velocity is zero. , therefore
a = V^2/(2 X)= 1.664 m/s^2
Here's how you can derive it (if you can't remember it).
Average velocity = V/2
Time T = X/(V/2) = 2 X/V
Acceleration a = V/T = V^2/(2 X)