CIE iGCSE Co-Ordinated Science P1.5.1 Effects of forces Exam Style Questions Paper 2
▶️ Answer/Explanation
The unloaded length is 4.0 cm. When loaded, length becomes 5.0 cm, so extension = 1.0 cm. From the extension-load graph, an extension of 1.0 cm corresponds to a load of 2.0 N (by reading the graph). Thus, the load is 2.0 N.
✅ Answer: (B)
✅ Answer: (B)
▶️ Answer/Explanation
The spring constant \(k\) is given by \(k = \frac{F}{x}\), where \(F\) is the load and \(x\) is the extension. The extension is the change in length: \(x = 20 – 16 = 4 \text{ cm}\). The change in load is \(\Delta F = 20 – 12 = 8 \text{ N}\). Therefore, \(k = \frac{8}{4} = 2.0 \text{ N/cm}\).
✅ Answer: (C)
✅ Answer: (C)
▶️ Answer/Explanation
The forces act in opposite directions along the same straight line. To find the resultant, subtract the smaller force from the larger force. The direction of the resultant is the direction of the larger force. Resultant force \(= 800 – 500 = 300 \text{ N}\) to the right (since 800 N is greater than 500 N and acts to the right).
✅ Answer: (B)
✅ Answer: (B)
▶️ Answer/Explanation
Weight of rocket = \(mg = 300 \times 10 = 3000\text{ N}\) acting downwards, opposing the 12 000 N thrust.
Resultant force \(= 12000 – 3000 = 9000\text{ N}\) upwards.
Using (F = ma): \(a = \frac{9000}{300} = 30\text{ m/s}^2\).
✅ Answer: (A)
Resultant force \(= 12000 – 3000 = 9000\text{ N}\) upwards.
Using (F = ma): \(a = \frac{9000}{300} = 30\text{ m/s}^2\).
✅ Answer: (A)
▶️ Answer/Explanation
The springs are in series, so the full 1.0 N load acts on each individual spring.
Using the spring constant from \(k = \frac{3.0\text{ N}}{3.0\text{ cm}} = 1.0\text{ N/cm}\), each spring extends by \(\frac{1.0\text{ N}}{1.0\text{ N/cm}} = 1.0\) cm.
With three springs each extending 1.0 cm, the total extension is \(3 \times 1.0 = 3.0\) cm.
✅ Answer: (B)
Using the spring constant from \(k = \frac{3.0\text{ N}}{3.0\text{ cm}} = 1.0\text{ N/cm}\), each spring extends by \(\frac{1.0\text{ N}}{1.0\text{ N/cm}} = 1.0\) cm.
With three springs each extending 1.0 cm, the total extension is \(3 \times 1.0 = 3.0\) cm.
✅ Answer: (B)