ELECTRIC MOTORS AND ELECTROMAGNETIC INDUCTION
3 marks · EasyA student wishes to investigate how the force on a wire in a magnetic field changes when they change the current and the strength of the field.
State two variables the student can change to increase the force acting on the wire.
State one way the student could decrease the force on the wire.
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(a) Increase the current in the wire, increase the strength of the magnetic field.
(b) Reduce the current or use a weaker magnetic field.
Show mark scheme and worked solution
Marking points
B1 (a) · 1 mark · One correct variable given (e.g., current).
B1 (a) · 1 mark · Second correct variable (e.g., field strength).
B1 (b) · 1 mark · Correct way to decrease the force (reduce current or field strength).
Worked solution
a) Increase the current; increase the magnetic field strength. b) Reduce the current or use a weaker magnetic field.