Question

What will happen to the current passing through a conductor if the potential difference is doubled and the resistance is halved?

• A. Remains unchanged
• B. Becomes doubled
• C. Becomes halved
• D. Becomes four times

Answer 1

The correct option is D

Becomes four times

Step 1: Given data

Initial potential difference $=V_1$

Final potential difference,$V_2=2V_1$

Initial resistance $=R_1$

Final resistance, $R_2=\frac{R_1}{2}$

Initial current $=I_1$

Final current, $I_2=?$

Step 2: Formula used

$I_2=\frac{V_2}{R_2}$ ………………………….(a)

$I_1=\frac{V_1}{R_1}$ ………………………….(b)

Step 3: Calculation of the final current

Substituting the given values in equation (a), we get

$I_2=\frac{2V_1}{{\displaystyle \frac{R_1}{2}}}$

$I_2=4\frac{V_1}{R_1}$ ………………………(c)

Using equation (b) in equation (c), we get

$I_2=4\times I_1$

Hence, option (D) is correct.