Question

an electrical bulb is labelled 100w,240v. calculate A. the current through the filament when the bulb works normally B. the resistance of the filament used in the bulb​

Answer 1

Answer:

A = 0.42 A

B = 576 Ω

Explanation:

Given :-

Power = 100 w

Volt = 240 v

Current = i let

Resistance = r let

We know that ,

P = v*i

100 = 240*i

i = 100/240

i = 0.42 A ( approx)

Also,

P = v²/r

r = v²/P

r = 240*240/100

r = 576 Ω