12 exam-style questions (57 marks) in three tiers. Try each one on paper first, then check the model answer and mark scheme.
Chapter 5 notes12 questions · 57 marks
Showing 12 of 12 questions
Recall and simple application
State the equation for the moment of a force about a pivot, and give its unit.
Calculate the moment of a 60 N force acting 0.50 m from a pivot, perpendicular to the lever.
State the principle of moments.
Mark on a described diagram: the centre of gravity of a uniform metre rule.
Structured, exam-style
A spanner 20 cm long has a 90 N force applied at its end, perpendicular to it. (a) Calculate the moment about the bolt. (b) State what happens to the moment if the same force is applied at half the distance.
A uniform metre rule is pivoted at its centre. A 4.0 N weight hangs at the 30 cm mark. (a) Calculate the anticlockwise moment. (b) Calculate where a 6.0 N weight must hang on the right to balance.
Explain, using moments, why a long spanner loosens a tight bolt more easily than a short one.
Data, evaluation and explanation
A uniform metre rule of weight 1.4 N is pivoted at the 30 cm mark. What weight must hang at the 80 cm mark to balance the rule?
A non-uniform metre rule balances on a knife-edge at the 45 cm mark with no weights attached. (a) State what this shows about the rule's centre of gravity. (b) A 2.0 N weight is hung at the 15 cm mark. Calculate the weight that must be hung at the 95 cm mark to restore balance, and verify it by calculating both moments.
A wheelbarrow carries a 600 N load whose weight acts 0.40 m from the wheel axle. The gardener)s hands lift the handles 1.2 m from the axle. (a) Calculate the upward force the gardener applies. (b) Explain why the wheelbarrow makes the load feel lighter.
Two children sit on a seesaw: 250 N at 1.6 m left of the pivot and 400 N at 0.80 m right. (a) Show whether the seesaw balances. (b) State which side tips and why. (c) The 400 N child moves 0.20 m closer to the pivot. Recalculate and state the new state of balance.
A crane arm is 6.0 m long, pivoted at the base. A load of 5000 N hangs at 4.0 m from the pivot. (a) Calculate the moment of the load. (b) A cable pulls the arm)s far end to hold it steady. Calculate the required pull, assuming it acts perpendicular to the arm at 6.0 m. (c) State what happens to the required pull if the cable is attached only 3.0 m out.
Next step
A 30-mark paper set out like a school paper, with a separate mark scheme. Give yourself 40 min.
Question paper
30 marks · 40 min · 4 pages
5 multiple-choice questions and structured questions with answer lines. Chapter 5 (moment = force × perpendicular distance, principle of moments, centre of gravity of uniform rules).
Mark scheme
PROAnswers · Marking points · 2 pages
Model answers with a mark for each creditworthy point — for marking at home or in class.