The velocity of a skateboarder moving in a straight line is recorded at three instants:
0s:3m/s, 2s:9m/s, 5s:−3m/s (opposite direction to the initial motion).
Calculate the following:
(a) Average acceleration during the first 2s.
(b) Average acceleration during the next 3s.
(c) Average acceleration for the entire 0–5s interval and state its sign.