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