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?

1 Answer
Feb 14, 2016

Yes; the current produced (#1 1/3 Amperes#) is less than the maximum permitted by a #6A# fuse.

Explanation:

#12V# applied to a circuit with a resistance of #9Omega#
will generate #(12V)/(9Omega) = 4/3 Amps# of current.

I like to think of it in the form
#color(white)("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
#color(white)("XXX")("Voltage")/("Current"xx"Resistance")=1# (there is even a diagram for this)