AQA
A-LEVEL
PHYSICS
Paper 3
7408/3BE
Electronics
MAY 2023
CONTENT ON NEXT PAGE
[MERGED]
, Please write clearly in block capitals.
Centre number Candidate number
Surname
Forename(s)
Candidate signature
I declare this is my own work.
A-level
PHYSICS
Paper 3
Section B Electronics
Thursday 15 June 2023 Morning Time allowed: The total time for
Materials
both sections of this paper is
For this paper you must have: 2 hours. You are advised to
• a pencil and a ruler spend approximately
• a scientific calculator
• a Data and Formulae Booklet 50 minutes on this section.
• a protractor.
For Examiner’s Use
Instructions
• Use black ink or black ball-point pen. Question Mark
• 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
outside the box around each page or on blank pages. 3
• If you need extra space for your answer(s), use the lined pages at the end of 4
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
to be marked. TOTAL
• 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.
*JUN2374083BE01*
IB/M/Jun23/E9 7408/3BE
, 2
Do not write
outside the
Section B box
Answer all questions in this section.
0 1 Figure 1 shows the input and output pins for a 4-bit binary counter. The output pin for
the least significant bit is A.
Figure 1
0 1 . 1 Complete Figure 1 by adding a single logic gate to the binary counter so that the
circuit functions as a modulo-6 counter.
[2 marks]
Figure 2 shows three outputs of the modulo-6 counter connected to a logic
sub-system that controls a 7-segment display.
The decimal point on the display is not shown.
The whole system shown in Figure 2 is to be used as an electronic dice.
Figure 2
Segments in the 7-segment display are turned on or off by the logic sub-system
to display the decimal numbers 1 to 6 in sequence.
A segment in the display turns on when the logic output with the same letter as the
segment is at logic 1.
*02*
IB/M/Jun23/7408/3BE
, 3
Do not write
outside the
Table 1 shows how the values of CBA control the logic level applied to each of the box
segments a to g during the counting cycle.
Table 1
Logic inputs Logic outputs
C B A a b c d e f g
0 0 0 0 1 1 0 0 0 0
0 0 1 1 1 0 1 1 0 1
0 1 0 1 1 1 1 0 0 1
0 1 1 0 1 1 0 0 1 1
1 0 0 1 0 1 1 0 1 1
1 0 1 1 0 1 1 1 1 1
0 1 . 2 One of the logic outputs a to g is controlled by a single NOT gate. This gate uses one
of the inputs A, B or C.
State the input that is used and the segment that this NOT gate controls.
[1 mark]
input =
segment =
0 1 . 3 X represents one of the logic outputs. The Boolean expression for this output is:
X = ( A ⋅ B) + C
State which of the logic outputs a to g is being controlled by this function.
[1 mark]
logic output =
Question 1 continues on the next page
Turn over ►
*03*
IB/M/Jun23/7408/3BE
A-LEVEL
PHYSICS
Paper 3
7408/3BE
Electronics
MAY 2023
CONTENT ON NEXT PAGE
[MERGED]
, Please write clearly in block capitals.
Centre number Candidate number
Surname
Forename(s)
Candidate signature
I declare this is my own work.
A-level
PHYSICS
Paper 3
Section B Electronics
Thursday 15 June 2023 Morning Time allowed: The total time for
Materials
both sections of this paper is
For this paper you must have: 2 hours. You are advised to
• a pencil and a ruler spend approximately
• a scientific calculator
• a Data and Formulae Booklet 50 minutes on this section.
• a protractor.
For Examiner’s Use
Instructions
• Use black ink or black ball-point pen. Question Mark
• 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
outside the box around each page or on blank pages. 3
• If you need extra space for your answer(s), use the lined pages at the end of 4
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
to be marked. TOTAL
• 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.
*JUN2374083BE01*
IB/M/Jun23/E9 7408/3BE
, 2
Do not write
outside the
Section B box
Answer all questions in this section.
0 1 Figure 1 shows the input and output pins for a 4-bit binary counter. The output pin for
the least significant bit is A.
Figure 1
0 1 . 1 Complete Figure 1 by adding a single logic gate to the binary counter so that the
circuit functions as a modulo-6 counter.
[2 marks]
Figure 2 shows three outputs of the modulo-6 counter connected to a logic
sub-system that controls a 7-segment display.
The decimal point on the display is not shown.
The whole system shown in Figure 2 is to be used as an electronic dice.
Figure 2
Segments in the 7-segment display are turned on or off by the logic sub-system
to display the decimal numbers 1 to 6 in sequence.
A segment in the display turns on when the logic output with the same letter as the
segment is at logic 1.
*02*
IB/M/Jun23/7408/3BE
, 3
Do not write
outside the
Table 1 shows how the values of CBA control the logic level applied to each of the box
segments a to g during the counting cycle.
Table 1
Logic inputs Logic outputs
C B A a b c d e f g
0 0 0 0 1 1 0 0 0 0
0 0 1 1 1 0 1 1 0 1
0 1 0 1 1 1 1 0 0 1
0 1 1 0 1 1 0 0 1 1
1 0 0 1 0 1 1 0 1 1
1 0 1 1 0 1 1 1 1 1
0 1 . 2 One of the logic outputs a to g is controlled by a single NOT gate. This gate uses one
of the inputs A, B or C.
State the input that is used and the segment that this NOT gate controls.
[1 mark]
input =
segment =
0 1 . 3 X represents one of the logic outputs. The Boolean expression for this output is:
X = ( A ⋅ B) + C
State which of the logic outputs a to g is being controlled by this function.
[1 mark]
logic output =
Question 1 continues on the next page
Turn over ►
*03*
IB/M/Jun23/7408/3BE
