# A circuit with a resistance of 9 Omega has a fuse melts at 6 A. Can a voltage of 12 V be applied to the circuit without blowing the fuse?

Feb 14, 2016

Yes; the current produced ($1 \frac{1}{3} A m p e r e s$) is less than the maximum permitted by a $6 A$ fuse.

#### Explanation:

$12 V$ applied to a circuit with a resistance of $9 \Omega$
will generate $\frac{12 V}{9 \Omega} = \frac{4}{3} A m p s$ of current.

I like to think of it in the form
$\textcolor{w h i t e}{\text{XXX")"Current" = ("Voltage")/("Resistance}}$
since it seems obvious to me that increasing the voltage should increase the current and increasing the resistance should decrease the current.

However some people prefer:
color(white)("XXX")"Voltage" = "Current"xx"Resistance"
or
$\textcolor{w h i t e}{\text{XXX")("Voltage")/("Current"xx"Resistance}} = 1$ (there is even a diagram for this)