Thread: A variation problem

The current flowing in an electrical circuit at a constant potential varies inversely as the resistance of the circuit. If the current is 25 amperes when the resistance is 4 ohms, what is the current when the resistance is 5 ohms?

What is the answer?

Is the answer 20?

Hello,

The current I variates inversely as the resistance R.

This means that there exists k such as :

I=k/R -> k=RI

For I=25, R=4.

And you want to know I' if R'=5.

So I'=k/R'=RI/R'=4*25/5=20

Originally Posted by mt_lapin

Is the answer 20?

Yep