Question

2. A constant force changes the speed of a 100kg sprinter from 4.0m/s to 6.0 m/s in 1.0 s. Calculate
a) The acceleration of the sprinter during this time.
b) The magnitude of the force

Answer 1

(a) The acceleration of the sprinter

$$a=\frac{\Delta v}{\Delta t}=\frac{6.0\:\rm m/s-4.0\: m/s}{1.0\:\rm s}=2.0\:\rm m/s^2$$

(b) The magnitude of the force

$$F=ma=100\:\rm kg\times 2.0\: m/s^2=200\: N$$