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Question
A fuse is rated 5 A. Can it be used with a geyser rated 1540 W, 220 V Write Yes or No. Give supporting calculations to justify your answer.
Solution
Here, power of geyser is P = 1540 W
Voltage, V = 220 V
Now, P = VI
or current drawn, I = `P/V`
= `1540/220`
= 7A
Because a geyser pulls more current than the fuse can handle, a 5A fuse will blow if used with one. No, you cannot use a 5A fuse.
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