10 questions · Form 4 Mathematics Bab 7: Graphs of Motion
A cyclist moves according to a distance-time graph. The distance increases from 0 km to 12 km in 0.5 hours. What is the speed in km/h?
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1. A cyclist moves according to a distance-time graph. The distance increases from 0 km to 12 km in 0.5 hours. What is the speed in km/h?
Answer: C
Speed = Gradient = 12 - 00.5 - 0 = 24 km/h.
2. If a vehicle accelerates from 10 m/s to 30 m/s in 5 seconds, what is its acceleration?
Answer: B
Acceleration = v - ut = 30 - 105 = 205 = 4 m/s².
3. What physical quantity does the area under a speed-time graph represent?
Answer: C
The area enclosed under a speed-time graph and the time axis equals the total distance traveled.
4. A car travels 150 km in 2.5 hours. What is its average speed in km/h?
Answer: B
Average Speed = Total Distance / Total Time = 150 km / 2.5 h = 60 km/h.
5. If an object has an initial speed of u m/s and comes to rest after t seconds with acceleration a, which equation represents the relationship?
Answer: B
Final speed v = 0. Acceleration a = v - ut = 0 - ut = -ut.
6. If a motorcycle decelerates from 25 m/s to a complete stop in 10 seconds, what is its rate of deceleration?
Answer: B
Acceleration = 0 - 2510 = -2.5 m/s². The rate of deceleration (magnitude of slowing down) is 2.5 m/s².
7. What is the formula for calculating average speed from a distance-time graph?
Answer: B
By definition, Average Speed is always calculated as Total Distance Covered divided by Total Time Taken.
8. If the gradient of a speed-time graph is zero during a 12-second interval, what is the acceleration during that time?
Answer: C
Gradient of speed-time graph represents acceleration. Zero gradient means zero acceleration.
9. A runner accelerates from 0 to 8 m/s in 4 seconds, runs at 8 m/s for 10 seconds, and stops in 2 seconds. What is the total distance covered?
Answer: B
Total time = 4 + 10 + 2 = 16 s. Flat top duration = 10 s. Area of trapezium = 12 × (10 + 16) × 8 = 12 × 26 × 8 = 104 m.
10. What does a horizontal line on a speed-time graph signify?
Answer: B
A horizontal line on a speed-time graph means the speed remains constant over time (zero acceleration).