Safety devices
3 marks · EasyA student is learning how different safety features protect a user of an electrical appliance.
State the purpose of a fuse in an electrical plug.
What happens to the fuse if too much current flows through the circuit?
Explain how this helps keep the user safe.
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
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(a) To break the circuit if the current is too high / to protect appliances or users from too much current.
(b) It melts (blows) and breaks the circuit.
(c) Stops current flowing, preventing electric shock or fire.
Show mark scheme and worked solution
Marking points
B1 (a) · 1 mark · Correctly states the main purpose of a fuse.
B1 (b) · 1 mark · Describes correct fuse action if current gets too high (e.g. melts, blows, breaks circuit).
B1 (c) · 1 mark · Explains why fuse action keeps user safe (e.g. prevents shock/fire, stops current reaching user).
Worked solution
a) The fuse is used to break the circuit if too much current flows, protecting the device and user.
b) The fuse wire melts or 'blows', breaking the circuit.
c) Stopping the current prevents electric shocks or fires by ensuring dangerous currents do not flow through the appliance.