Form 2 Science Chapter 10
FORM 2 CHAPTER 10 SIMPLE MACHINE
1. Diagram 1.1 shows a wheelbarrow.
Diagram 1.1 (a) On Diagram 1.1, label the position of the fulcrum. [1 mark] (b)(i) Based on Diagram 1.1, state the class of lever of the wheelbarrow. …………………………………………………………………………………………………. [1 mark] (ii) Give one reason for your answer in (b)(i). …………………………………………………………………………………………………. [1 mark] (c) Based on Diagram 1.2, choose one tool with the same class of lever as the wheelbarrow in Diagram 1.1. Mark (√ ) in the box for the tool.
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Diagram1.2 [1 mark] (d) Diagram 1.3 shows the situation when a force and a load are balanced.
Diagram 1.3 (i) Calculate force P needed to balance the metre rule. Use the following fomula: Load x Distance of load form fulcrum = Force x Distance of force form the fulcrum
[3 marks]
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(ii) What happens to the value of P if the load is moved nearer to the fulcrum? …………………………………………………………………………………………………. [1 mark]
2. Diagram 2.1 shows a claw hammer.
Q: ……………………….
P: ………………………
R: ………………………
Diagram 2.1 (a) Label P, Q and R on Diagram 2.1 using the following words. Fulcrum
Load
Effort [3 marks]
(b) (i) What is the class of this lever system? …………………………………………………………………………………………………… [1 mark] (ii) State one reason for your answer in (b)(i). ……………………………………………………………………………………………………
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[1 mark]
(c) Calculate the moment of force in Diagram 2.2 if a force of 50 N is exerted to pull the nail. Moment of force (Nm) = Force (N) X Perpendicular distance (m)
Diagram 2.2
[2 marks]
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3. Diagram 3 shows levers P, Q, R and S. P
Q
R
S
Diagram 3 (a) Based on the observations in Diagram 3, state the class of lever P, Q, R and S. P: …………………………………………………………………………………………………… Q ……………………………………………………………………………………………………. R ……………………………………………………………………………………………………. S ……………………………………………………………………………………………………. [4 marks]
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(b) Classify levers P, Q, R and S into two groups based on common properties. Give examples of levers belonging to each group. P, Q, R and S
Common property
Alphabets representing the levers
[4 marks]
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4. Diagram 4 shows spanners P and Q which are used to tighten the nut at different time.
Spanner P
0.1 m
Spanner Q
Force
Force
0.2 m
Diagram 4 (a) (i) Which spanner will produce a greater turning effect? ………………………………………………………………………………………………… [1 mark] (ii)
Explain your answer in (a)(i). …………………………………………………………………………………………………. …………………………………………………………………………………………………. [1 mark]
(b) What are the factors that affect the moment of force? (i)
…………………………………………………………………………………………… ……
(ii)
…………………………………………………………………………………………… …… [2 marks]
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(c) Calculate the moment of force on spanner P if a force of 20 N is used.
[2 marks] 5. Diagram 5.1 shows Kok Meng and Ranjit on a see-saw. Kok Meng is 50 kg. He sits 120 cm from the fulcrum of the see-saw. The see-saw is in balanced when Ranjit who is 60 kg sits on the other end of the see-saw.
Diagram 5.2
(a) (i) Name the class of lever shown in the Diagram 5. ………………………………………………………………………………………………………. [1 mark] (ii) Find the distance of Ranjit from the fulcrum.
[2 marks] (iii) If Ranjit and another friend sit at the same end, what should Kok Meng do to balance the see-saw?
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…………………………………………………………………………………………………… [1 mark]
(b) Diagram 5.2 shows a pair of ice tongs.
Ice cube
(i)
What class of lever is the ice tong? ………………………………………………………………………………………………….. [1 mark]
(ii) At which point, A, B, C or D is the biggest effort needed to hold the ice cube? Why? ………………………………………………………………………………………………….. …………………………………………………………………………………………………... [2 marks] (iii)
What is the relationship between the effort and the effort arm? ………………………………………………………………………………………………. ……………………………………………………………………………………………… [1 mark]
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