Answer to Question #208608 in Classical Mechanics for Mimi

Question

A truck’s speed increases uniformly from 15 km/h to 60 km/h in 20 s. Determine (a) the average speed, (b) the acceleration, and (c) the distance travelled, all in units of meters and seconds.

Answer 1

(a) The average speed:

$$v=\frac{v_1+v_2}{2}=10.4\text{ m/s}.$$

(b) The acceleration:

$$a=\frac{v_2-v_1}{t}=0.625\text{ m/s}^2.$$

(c) The distance is

$$d=\frac{v_2^2-v_1^2}{2a}=208\text{ m}.$$