Question
A 5 amp fuse wire can withstand a maximum power of 1 W in circuit. The resistance of the fuse wire is
0.2 Ω
5 Ω
0.4 Ω
0.04 Ω
Solution
D.
0.04 Ω
Electric power = volltage difference × current
P = i V
= i × iR
⇒ Power P = i2 R
⇒ R =
Given:- P = 1W and i = 5A
∴ R =
R = 0.04 Ω