Q24 · 2022 · Paper 1Simple familiar3 marks
QUESTION 24 (3 marks)
A rectangular loop is placed in a uniform magnetic field of 5 mT.
Calculate the change in flux through the loop when it is rotated around the vertical axis. Show your working.
WORKED SOLUTION
3 marksQCAA guide · typeset solution
ANSWER
See worked solution below.
Worked solution
If loop is rotated 60°, angle of the loop perpendicular to the
magnetic field is 90° −60° = 30°
3
5 10
0.06
s
cos
4
2.6
0
1
o
0
c
3
Wb
BA
φ
θ
=
−
=
×
−
=
×
×
×
°
Change in flux = 2.6 × 10−4 Wb (to two significant figures)
• identifies the angle of the loop perpendicular to
the magnetic field [1 mark]
• recognises the scenario relates to the amount of
magnetic flux passing through an area [1 mark]
• calculates the change in flux [1 mark]
One QCAA sample method typeset for web; criterion wording is adapted from the official marking guide.
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Compare your working with the guide above.