Pearson Edexcel International GCSE (9–1) · PHYSICS · Section
THE TURNING EFFECT OF FORCES
24 practice questions
Practice questions
1–10 of 24
Question 1
1 mark · Easy
Answer and see the solution →State the unit used for the moment of a force.
Question 2
1 mark · Easy
Answer and check →Which of the following statements about moments is correct?
- A.The moment of a force increases if the force is applied further from the pivot.
- B.The moment of a force does not depend on the distance from the pivot.
- C.Moments are measured in newtons (N).
- D.The moment of a force increases if the force is applied closer to the pivot.
Question 3
2 marks · Easy
Answer and see the solution →A child pushes horizontally with a force of 60 N on a swing seat, which is 0.4 m from the pivot. Calculate the moment of the force about the pivot.
Question 4
3 marks · Easy
Answer and see the solution →A see-saw is balanced. Child A weighs 250 N and sits 1.2 m from the pivot. Child B weighs 300 N. Both are seated on opposite sides of the pivot.
(a)[1 mark]Calculate the moment produced by Child A about the pivot.
(b)[2 marks]How far from the pivot must Child B sit to balance the see-saw?
Question 5
1 mark · Easy
Answer and see the solution →What is the name given to the point through which the weight of a body acts?
Question 6
2 marks · Easy
Answer and see the solution →Describe how you would find the centre of gravity of a rectangular sheet of card.
Question 7
3 marks · Easy
Answer and see the solution →A uniform plank of 2.0 m has negligible mass. It rests on two supports, one at each end. A heavy box weighing 120 N is placed 0.5 m from the left end.
(a)[1 mark]What is the total downward force acting on the supports?
(b)[2 marks]Calculate the upward force provided by the right-hand support.
Question 8
2 marks · Easy
Answer and see the solution →Look at the diagram below.
Beam with boy standing 0.5 m from the right end. A beam 2.0 m long is supported at ends P and Q. A 400 N boy stands 0.5 m from Q.
(a)[2 marks]How much of the boy's weight is supported by Q?
Question 9
4 marks · Normal
Answer and see the solution →A person tries to open a heavy gate by applying a force of 120 N perpendicular to the gate, 0.75 m from the hinge. Another person tries to keep the gate closed by pushing with a force of 180 N, but only 0.3 m from the hinge.
(a)[1 mark]Calculate the moment produced by the first person about the hinge.
(b)[1 mark]Calculate the moment produced by the second person about the hinge.
(c)[2 marks]State which person has a greater turning effect on the gate and explain your answer.
Question 10
4 marks · Normal
Answer and see the solution →The diagram shows a uniform beam of length 2.0 m and negligible mass balanced on two supports, A and B, at either end. A box of mass 20 kg is placed 0.5 m from support A.
Beam with supports and load (a)[1 mark]Draw a force diagram showing the forces acting on the beam.
(b)[2 marks]Taking moments about support A, calculate the upward force on support B due to the box only. (Take g = 10 N/kg.)
(c)[1 mark]State and explain how the upward forces at supports A and B would change if the box is moved closer to support B.