6.3 SPM Practice (Long Questions)

Question 3:
Diagram below shows the distance-time graph for the journey of a train from one town to another for a period of 90 minutes.


(a) State the duration of time, in minutes, during which the train is stationery.
(b) Calculate the speed, in km h^-1, of the train in the first 40 minutes.
(c) Find the distance, in km, travelled by the train for the last 25 minutes.

Solution:
(a) Duration the train is stationery = 65 – 40 = 25 minutes

$\begin{array}{l}\text{(b)}\\ \text{Speed of the train in the first 40 minutes}\\ =\frac{150-90\text{ km}}{40\text{ minutes}}\\ =\frac{60\text{ km}}{\frac{40}{60}\text{ h}}\\ =90\text{ km / h}\end{array}$

(c) 90 – 0 = 90 km

Question 4:


Solution:
(a)
= 75 m

(b)
Average speed for the whole journey
$\begin{array}{l}=\frac{\text{Total distance travelled}}{\text{Total time taken}}\\ =\frac{75}{10}\\ =7.5m{s}^{-1}\end{array}$