When a battery is connected to the resistance of `10 Omega` the current in the circuit is 0.12 A . The same battery gives 0.07A current with `20 Omega` Calculate e.m.f and internal resistance of the battery.

Explanation

To solve the problem of finding the e.m.f (electromotive force) and internal resistance of the battery, we can follow these steps:

### Step 1: Set Up the Equations
We know from Ohm's law that the e.m.f (E) of the battery can be expressed in terms of the current (I), external resistance (R), and internal resistance (r) as follows:
\[ E = I \cdot R + I \cdot r \]
This can be rearranged to:
\[ E = I(R + r) \]

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