3e S(phy) Test On Kinematics & Dynamics

Name: ……………………………….(

)

Date: …………….. 30

Class: ………… 3E Sc(Physics) Class Test 3 Multiple Choice (5m) Answer all questions in the spaces provided. 1.

Which of the following is a scalar quantity? A Force B Displacement C Distance D Velocity Answer: …………………

2.

In which of the following is a force of friction necessary? A When a ball is bouncing off a wall B When a drum skin is vibrating C When a rocket is taking off D When a car is accelerating Answer: ……………………

3.

A bunch of keys is thrown vertically upwards into the air. Which one of the following graphs best represents the motion of the keys from the moment they are thrown to the moment they are caught?

1

Answer: ……………………

4.

The diagram below shows the speed-time graph of a car. Which section of the graph shows the car moving with increasing acceleration?

Answer: …………………

5.

A man pulls a string attached to a 3.00 kg box. The box moves horizontally with constant speed 2 cm/s. Take g as 10.0 m/s2.

2 C

DB

Which diagram shows correctly all the forces acting on the box ?

A

Answer: ……………………

Structured Questions (25m) Answer all questions in the spaces provided.

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6.

The graph below represents the motion of car A along a straight road. As car A approaches a small town, it slows down. It travels at a constant speed from the start of the town to the end of the town. After passing through the town, the car speeds up.

(a)

What is the highest speed of car A throughout the whole journey?

[1]

(b)

What is the distance between the start and the end of the town?

[2]

(c)

Calculate the average speed of car A for the first 12 s of its journey.

[3]

(d)

What is the deceleration of car A between 8 s and 12 s?

[2]

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(e)

Car B is stationary on the road at the time where car A reaches the start of the town. It accelerates uniformly for 30 s and reaches a speed of 10 m/s. (i) On the graph, draw the speed-time graph of car B. (ii) Determine whether car B reaches the end of the town in 30 s.

7.

[1] [2]

A girl walked a short distance to the market. The distance–time graph represents her walk.

(a)

Choose phrases from the box to complete the sentences. (i) Between A and B she was ................................................................…………..

[2]

…………………………………………………………………………………………. (ii) Between B and C she was .................................................................………….. ……………………………………………………………………………….………….. (b)

Complete the sentence.

[1]

You can tell that the girl’s speed between A and B was .............................. than her speed between C and D because ...................................…….....……………………. ……………………………………………………………………………………………….

8.

A force of 10 N acts on a mass of 2 kg. 5

(a)

Calculate the acceleration which should be produced.

(b)

If the acceleration if found to be only 3 m/s2, suggest why this value is less than

[2]

expected. Explain your answer.

9.

[1]

The speed of a cyclist moving along a horizontal straight road is shown in the diagram below.

(a)

How does the graph above indicate that the cyclist had a constant acceleration for the first 20 s?

[1] 6

(b)

Calculate the resultant force acting on the cyclist between 20 s and 30 s.

[2]

10. James makes a parachute out of a square piece of polythene. He attaches it to a 20 g mass. He drops the parachute. The main forces acting on the parachute are shown in this diagram.

(a)

Name force A and B.

[1]

Force A: …………………………………………. (b)

Force B: …………………………………………. Calculate force B.

[2]

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(c)

If the parachute is moving upwards at constant speed, state the value of force A. Explain your answer.

[2]

Value of force A: ………………… Explanation: ……………………………………………………..…………………………. ………………………………………………………………………………………………..

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