Brett stats from rest on his skateboard and accelerates at 0.5 m/s2 [N] for 12s, and then maintains his velocity for 15s before falling off his board. He slides along on his back until he comes to rest, accelerating at -2.4 m/s2.

Question

a) Calculate the highest instantaneous velocity that Brett reaches.
b) How long did it take Brett to come to rest after falling?
c) Draw a velocity-time graph for the total time.
d) What is his displacement in the first 12s?
e) What is his displacement while maintaining a constant velocity?
f) What is his displacement after he fell?
g) What is Brett’s average velocity over the total time?

Answer 1

a) v = at
b) t = v/a
d) x = 1/2 at^2
e)x = vt
f) x = 1/2at^2
g) v = total dist/total time