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प्रश्न
An electric kettle consumes 1 kW of electric power when operated at 220 V. A fuse wire of what rating must be used for it?
विकल्प
1A
2A
4A
5A
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उत्तर
5A
Explanation -
Power (P) = 1 kW = 1000 W
Potential difference (V) = 220 V
We know,
P = VI
`"I" = "P"/"V"`
`"I" = 1000/220`
I = 4.54 A
From all the given options, 5 A fuse wire is correct.
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