Physics
(i) A fuse is rated 8A. Can it be used with an electrical appliance rated 5 KW, 200 V? Give a reason.
(ii) Name two safety devices which are connected to the live wire of a household electric circuit.
Household Circuits
ICSE 2018
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Answer
Given,
P = 5 KW = 5000 W,
V = 200 V
Current drawn i = = = 25 A
Since, the appliance when in use will draw 25 A current, the fuse rated 8 A cannot be used because it will blow off as the current will exceed 8 A and the circuit wil break.
(ii) Safety devices which are connected to the live wire of a household electric circuit are switch and fuse.
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