$A$ truck is moving on a straight road with uniform acceleration. The following table gives the speed of the truck at various instants of time.

Speed $(m s^{-1})$	$5$	$10$	$15$	$20$	$25$	$30$
Time $(s)$	$0$	$10$	$20$	$30$	$40$	$50$

Draw the speed-time graph by choosing a convenient scale. Determine from it:
$(i)$ The acceleration of the truck.
$(ii)$ The distance travelled by the truck in $50$ seconds.

(N/A) The speed-time graph is a straight line starting from $(0, 5)$ to $(50, 30)$.
$(i)$ Acceleration is the slope of the speed-time graph.
Slope $= \frac{\text{Change in speed}}{\text{Change in time}} = \frac{30 - 5}{50 - 0} = \frac{25}{50} = 0.5 \ m s^{-2}$.
$(ii)$ The distance travelled is the area under the speed-time graph.
This area forms a trapezium with parallel sides of length $5 \ m s^{-1}$ and $30 \ m s^{-1}$, and height (time) of $50 \ s$.
Area $= \frac{1}{2} \times (\text{sum of parallel sides}) \times \text{height}$
Area $= \frac{1}{2} \times (5 + 30) \times 50 = \frac{1}{2} \times 35 \times 50 = 35 \times 25 = 875 \ m$.