Question:medium

When an external resistor of resistance $18\,\Omega$ is connected to a cell, the current drawn from the cell is $I$. If another $18\,\Omega$ resistor is connected parallel to the first resistor, the current drawn from the cell increases by $90\%$, then the internal resistance of the cell is

Show Hint

For a cell, \[ I=\frac{E}{R+r}. \] Whenever the external resistance changes, write the current expression before and after the change, then use the given percentage increase/decrease to determine the internal resistance.

Updated On: Jul 29, 2026

$2\,\Omega$
$0.5\,\Omega$
$1.5\,\Omega$
$1\,\Omega$

Show Solution

The Correct Option is D

Solution and Explanation

Was this answer helpful?

Questions Asked in AP EAPCET exam

Let \[ f(x)=\int \frac{\sqrt{x}}{(1+x)^2}\,dx \quad (x\geq 0) \] Then \[ f(3)-f(1) \] is equal to:

AP EAPCET - 2026
Definite and indefinite integrals

View Solution

Gas is being pumped into a spherical balloon at the rate of $ 30 \, \text{ft}^3/\text{min} $. Then the rate at which the radius increases when it reaches the value $ 15 \, \text{ft} $ is:

AP EAPCET - 2026
Differentiation

View Solution

Let the function $ f(x) $ be defined as $ f(x) = \frac{x - |x|}{x} $, then:

AP EAPCET - 2026
Definite and indefinite integrals

View Solution

If the direction ratios of two lines are given by $ l + m + n = 0 $ and $ mn - 2ln + lm = 0 $, then the angle between the lines is:

AP EAPCET - 2026
3D Geometry

View Solution

When an external resistor of resistance \(18\,\Omega\) is connected to a cell, the current drawn from the cell is \(I\). If another \(18\,\Omega\) resistor is connected parallel to the first resistor, the current drawn from the cell increases by \(90\%\), then the internal resistance of the cell is

Show Hint

The Correct Option is D

Solution and Explanation

Top Questions on Current electricity

Questions Asked in AP EAPCET exam