A skateboarder, starting from rest, rolls down a 14.0-m ramp. When she arrives at the bottom of the ramp her speed is 7.40 m/s.

Question

(a) Determine the magnitude of her acceleration, assumed to be constant.

(b) If the ramp is inclined at 20.5° with respect to the ground, what is the component of her acceleration that is parallel to the ground?

please help! it would be much appreciated!!

Answer 1

a. V^2 = 2ad,
2ad = V^2,
2a*14 = (7.4)^2,
28a = 54.76,
a = 54.76/28 = 1.96 m/s^2.

b. a(hor) = 1.96*cos20.5 = 1.83 m/s^2.