Summative Practice (Question 1 & 2) – Form 4 Science (KSSM) Chapter 11

Question 1:


Azmeer rides his motorcycle to the north for 24 km, then to the west for 12 km and finally to the south for 12 km before he stops to rest (Figure 1). His journey takes 2 hours.

(a) What is the distance travelled by Azmeer?

(b) What is Azmeer’s displacement?

(c) Determine Azmeer’s average speed.

(d) Calculate the average velocity for Azmeer’s displacement.


Answer:
(a)
24 km + 12 km + 12 km = 48 km

(b)
$\begin{array}{l}\sqrt{{\left(12\text{ km}\right)}^2+{\left(12\text{ km}\right)}^2}\\ =16.97\text{ km to the northwest}\end{array}$


(c)
48 km ÷ 2 jam = 24 km j^–1

(d)
16.97 km ÷ 2 jam = 8.485 km j^–1

Question 2:
Hilmi walks to the north for 8 m, then to the east for 8 m. Hilmi takes 5 minutes to complete his journey.

(a) What is the distance of his motion?

(b) What is the displacement of his motion?

(c) Determine the velocity attained by Hilmi.

Answer:
(a)
8 m + 8 m = 16 m

(b)
$\begin{array}{l}\sqrt{{\left(8\text{ m}\right)}^2+{\left(8\text{ m}\right)}^2}\\ =11.31\text{ m to the northeast}\end{array}$

(c)
11.31 m ÷ (5 x 60 s) = 0.038 m s^–1