Question

In a circuit, if the resistance is doubled and the voltage is halved, what happens to the current flowing through the circuit?

• A. Becomes half
• B. Becomes quarter
• C. Becomes double
• D. Remains same

Hint:

Always use \( I = \frac{V}{R} \) when changes in voltage or resistance are given. A change in both parameters affects the current proportionally.

Answer 1

The Correct Option is B

Step 1: Recall Ohm’s Law. \[ I = \frac{V}{R} \] Let original voltage be \( V \), and resistance be \( R \), then the original current is: \[ I = \frac{V}{R} \] Step 2: Modify the values. New voltage \( V' = \frac{V}{2} \), and new resistance \( R' = 2R \) 
Step 3: Substitute into the current formula. \[ I' = \frac{V'}{R'} = \frac{V/2}{2R} = \frac{V}{4R} \] Step 4: Compare with original current. \[ I' = \frac{I}{4} \] So the new current becomes one-fourth of the original.