Pearson Edexcel International GCSE (9–1) · PHYSICS · Unit
Forces and Motion
367 practice questions
Topics covered
Practice questions
131–140 of 145 · Easy
Question 131
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 132
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 133
2 marks · Easy
Answer and see the solution →Describe how you would find the centre of gravity of a rectangular sheet of card.
Question 134
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 135
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 136
4 marks · Easy
Answer and see the solution →A car slows from 20 m/s to rest in 4 s when the brakes are applied. The car has a mass of 1000 kg.
(a)[2 marks]Calculate the acceleration of the car while braking.
(b)[2 marks]Calculate the braking force applied to the car.
Question 137
4 marks · Easy
Answer and see the solution →A block is pulled along a rough, horizontal surface. The block experiences a friction force and is stretched by a spring attached to it.
(a)[1 mark]Describe one effect of the friction force on the block as it moves along the surface.
(b)[2 marks]The spring attached to the block is stretched. State what will happen to the shape of the spring when the block is released and explain your answer.
(c)[1 mark]Name the type of force that causes the spring to return to its original shape.
Question 138
4 marks · Easy
Answer and see the solution →A trolley of mass 0.80 kg is pushed by a constant force of 2.0 N along a smooth, straight track.
(a)[2 marks]Calculate the acceleration of the trolley.
(b)[1 mark]Is the acceleration a vector or a scalar quantity? Explain your answer.
(c)[1 mark]State the unit for force.
Question 139
4 marks · Easy
Answer and see the solution →A student pushes a wooden block of mass 0.5 kg along a table. There is a force due to friction acting between the block and the table. The block is attached to a spring and a ruler is used to measure the extension of the spring as it moves.
(a)[1 mark]State one effect of friction on the motion of the block.
(b)[2 marks]The table below shows the force measured by the spring and the extension of the spring for different trials.
Force (N) Extension (cm) 0.0 0.0 1.0 1.4 2.0 2.8 3.0 4.2 State whether this spring obeys Hooke’s law in these trials. Give a reason for your answer.
(c)[1 mark]Describe what will happen to the extension of the spring if a larger force is applied and the spring is stretched beyond its elastic limit.
Question 140
4 marks · Easy
Answer and see the solution →A student is riding a bicycle. While pedalling, the student applies a forward force of 50 N. The friction and air resistance together produce a resisting force of 20 N.
(a)[1 mark]Calculate the resultant force acting on the bicycle.
(b)[2 marks]The mass of the bicycle and the student is 70 kg. Calculate the acceleration of the bicycle.
(c)[1 mark]Describe one way the student could increase the bicycle's acceleration without changing their mass.