Question

How must the voltage across a resistor change to reduce the current in the

Answer 1

Voltage must decrease by a factor of 3 to reduce the current in the resistor by a factor of 3

Answer: Option A

Explanation:

According to ohms law, the voltage passed in a circuit will be directly proportional to the current flow in the circuit. So the resistance of the resistor will act as proportionality constant in ohms law. Let us consider V as original voltage producing a current I in resistor of resistance R. Then according to ohms law:

                    $V=I \times R$

Now the revised current flow in the circuit is reduced by a factor of 3, So the new current is $\frac{I}{3}$ in the same resistance R, then the new voltage will be

                   $V^{\prime}=\frac{I \times R}{3}=\frac{V}{3}$

So, the voltage must be reduced by a factor of 3 to reduce the current in the resistor by a factor of 3.