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Lower Secondary Kinematics

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Although Kinematics is not exactly in the syllabus of lower secondary science, i realise that many schools has brought it down from upper secondary syllabus, teaching it in secondary 2. I believe this is to give students for time for O’Levels  revision in their final year. 🙂

Because Kinematics is not in lower secondary syllabus, questions on this topic can not be found in lower secondary assessment books.

Here are some of the questions i have come up with. (Aftering looking through some notes from different schools).

Jasmine & Jessie, i will be going through these questions with you two this week. 🙂

Kinematics

  1. Say what is acceleration to you ( Only proper English with science keywords will be accepted) 🙂

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2.    Write down the formulas for this chapter

3.   Dodo is going to buy stationary. He walked a distance of 2.5km at an average speed of 4km/h. He then feels pain in his stomach and wants to go to the nearest toilet. He run for a further 20 minutes with an average speed of 10km/h to reach the nearest toilet. What was the average speed of the whole journey?

4.   An ambulance accelerates at a rate of 7.5m/s from rest for 15s. What is its speed at the end of 10s?

5.   Brandon runs at a speed of 120km/h at the start of the race. He then accelerates uniformly at 3m/s2 for 15s.  Calculate the final speed of Brandon.

6.  Cindy is travelling at 35m/s when she suddenly sees an obstacle in the middle of the road ahead about 200m. Oops. Of course, any driver will try to avoid the obstacle, not crash onto it. Let’s see if Cindy is able to avoid the collision. Cindy’s reaction time is 0.7s (Remember during this interval, her speed is 35m/s). After the brakes were applied, the bus travelled a further 120m in 10s before stopping.

a.)Calculate the distance travelled during Cindy’s reaction time.

b.) Calculate the deceleration of Cindy

c.) Calculate the average speed of Cindy from the time she see obstacle to the time the car stopped.

d.) Did Cindy avoid the collision? Explain.

7.  Baba drives at an initial speed of 15m/s for 5s and then accelerates uniformly to 23m/s in 10s. He drives at his speed for another 7s. Finally, he decelerates uniformly in 17s before coming to a rest.

a) Draw a speed-time graph for the description of motion above.

b) Calculate the acceleration in the 10s.

c) Calculate the deceleration in the 17s.

d) Calculate the total distance moved and the average speed for Baba’s whole journey.

8. In a bumper car ring, a car is knocked and it accelerated. The car move a distance of 1.4m in 1.1s.

a) Calculate the average speed of this knocked car.

b) If the acceleration of this car is constant, calculate its speed after 1.1s

c) Calculate the acceleration of this knocked car.

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