Safety devices
2 marks · EasyA hairdryer is rated at 4 A. The plug contains a 3 A, 5 A and 13 A fuse.
Which fuse is the most suitable to use?
Explain your answer.
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(a) 5 A fuse
(b) It is the next size above 4 A, so will protect the appliance if the current becomes too high.
Common mistakes: Choosing the largest fuse
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Marking points
B1 (a) · 1 mark · Chooses 5 A fuse as suitable.
B1 (b) · 1 mark · Explains that 5 A fuse is just above appliance current and will blow if current is too high.
Worked solution
a) 5 A fuse.
b) Because the hairdryer uses 4 A, the 5 A fuse is the next highest standard size available and protects the appliance without blowing during normal use.