Question

A circuit with a resistance of `6 Omega` has a fuse that melts at `8 A`. Can a voltage of `42 V` be applied to the circuit without blowing the fuse?

Answer 1

The current flowing in a circuit can be calculated using Ohm's Law: `V=IR` or `I=V/R`. In this case the current is `7A`, so the fuse is safe.

Explanation:

Ohm's Law relates the current, `I (A)`, electrical potential difference (voltage), `V (V)` and resistance, `R (Omega)` in a circuit.

It is usually stated and remembered as `V=IR`.

Rearranging, `I=V/R = 42/6 = 7 A`

Since the fuse will blow (melt) if the current in the circuit is `8A` and the current is less than that, the fuse will not blow.