Question

(a) A runner starts from rest and in 2 s reaches a speed of 10 m/s. If we assume that the speed changed at a constant rate (constant net force), what was the average speed during this 2 s interval

Answer 1

Answer:

Average speed is 5 m/s

Explanation:

The initial speed = 0 m/s (since the runner starts from rest)

Final speed = 10 m/s

time interval = 2 sec

average speed = ?

The speed is assumed to change at a constant rate

Average speed = (final speed + initial speed)/2

==> (10 + 0)/2 = 10/2 = 5 m/s