A resistance of `97 Omega` is connected to a battery of emf 10 V . To measure the current passing in the circuit, an ammeter is inserted in series with the resistance. It is found that the ammeter reads 100 mA. What is the internal resistance of the battery if `2 Omega` is the resistance of ammeter ?

Explanation

To find the internal resistance of the battery, we can follow these steps:

### Step 1: Identify the known values
- Resistance of the external resistor, \( R = 97 \, \Omega \)
- EMF of the battery, \( E = 10 \, V \)
- Current measured by the ammeter, \( I = 100 \, mA = 0.1 \, A \)
- Resistance of the ammeter, \( r_a = 2 \, \Omega \)

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