2023 AQA A-level PHYSICS 7408/3BC Paper 3 Section B Engineering physics Question Paper & Mark scheme (Merged) June 2023 [VERIFIED]

2023 AQA A-level PHYSICS 7408/3BC Paper 3 Section B Engineering physics Question Paper & Mark scheme (Merged) June 2023 [VERIFIED] A-level PHYSICS Paper 3 Section B Engineering physics Thursday 15 June 2023 Morning Time allowed: The total time for Materials both sections of this paper is 2 hours. You are advised to For this paper you must have: • a pencil and a ruler spend approximately • a scientific calculator 50 minutes on this section. • a Data and Formulae Booklet • a protractor. For Examiner’s Use Instructions Question Mark • Use black ink or black ball-point pen. • Fill in the boxes at the top of this page. 1 • Answer all questions. 2 • You must answer the questions in the spaces provided. Do not write 3 outside the box around each page or on blank pages. 4 • If you need extra space for your answer(s), use the lined pages at the end of this book. Write the question number against your answer(s). 5 • Do all rough work in this book. Cross through any work you do not want TOTAL to be marked. • Show all your working. Information • The marks for questions are shown in brackets. • The maximum mark for this paper is 35. • You are expected to use a scientific calculator where appropriate. • A Data and Formulae Booklet is provided as a loose insert. *JUN2374083BC01* IB/M/Jun23/E7 7408/3BC 2 Section B Answer all questions in this section. 0 1 . 1 One equation used in translational dynamics is: force = mass × acceleration State in words the equivalent equation used in rotational dynamics. [2 marks] Figure 1 shows two identical uniform plates A and B. The axis of rotation of each plate is shown. Figure 1 0 1 . 2 State and explain which plate has the greater moment of inertia about its axis of rotation. [2 marks] Do not write outside the box *02* IB/M/Jun23/7408/3BC 3 An electric motor drives a machine that punches out plates from a long strip of sheet metal. The motor runs continuously and is fitted with a flywheel. Figure 2 shows how the angular velocity ω of the flywheel varies with time t. Figure 2 Table 1 describes the sequence for the machine after it has been brought up to speed ωA. Table 1 A The punching operation starts. A to B The flywheel transfers some of its energy during the punching operation. B to C The flywheel is again brought up to speed ωA by the motor. C The next punching operation starts. 0 1 . 3 A new flywheel with a greater moment of inertia is fitted in place of the original flywheel. The motor torque is constant and the same as before. Sketch on Figure 2 a graph showing how the angular velocity varies with time for the machine fitted with the new flywheel. Assume that: • the punching operation starts at the same angular speed ωA • the same quantity of energy is transferred when punching the metal sheet. [2 marks] Question 1 continues on the next page Turn over ► *03* Do not write outside the box IB/M/Jun23/7408/3BC 4 0 1 . 4Explain one difference between your graph and the original graph.