Question

Three fuse of rating 3a, 5a and 7a are available. Whichone of these will be most suitable to operate an electric ironof 1 kw power at 220 v electric line ? Give reason tojustify your answer.

Answer 1

The formula for solving this question will be I = P/E where I = current, P = power and E = electromotive force in volts.

Given -

P = 1kW = 1000W

V = 220

So, I = 1000/220 = 4.54A approx

So, the calculation is coming as 4.54 A. So, I guess the answer to this question will be 5A.

Hope this helps!!