When a battery connected across a resistor of `16 Omega`, the voltage across the resistor is 12 V. When the same battery is connected across a resistor of `10 Omega`, voltage across it is 11 V. The internal resistance of the battery (in ohm) is

Options

A. `10//7`
B. `20//7`
C. `25//7`
D. `30//7`

Explanation

To find the internal resistance of the battery, we can use the information provided about the voltage across the resistors and their values. Let's break down the solution step-by-step.

### Step 1: Understand the Circuit
When a battery is connected to a resistor, the voltage across the resistor can be described using Ohm's law. The total voltage (emf of the battery, \(E\)) is divided between the internal resistance (\(r\)) of the battery and the external resistor (\(R\)).

### Step 2: Set Up the Equations
For the first case with a resistor of \(16 \Omega\):
- Voltage across the resistor, \(V_1 = 12 V\)
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