A potentiometer wire of length 1 m has a resistance of `10Omega`. It is connected to a 6V battery in series with a resistance of `5Omega`. Determine the emf of the primary cell which gives a balance point at 40cm.

Explanation

To solve the problem step by step, we will follow the process of determining the emf of the primary cell using the given information about the potentiometer setup.

### Step 1: Understand the Setup
We have a potentiometer wire of length 1 m and resistance 10 Ω connected in series with a 5 Ω resistor to a 6 V battery. The balance point is found at 40 cm (0.40 m).

### Step 2: Calculate Total Resistance
The total resistance in the circuit can be calculated as follows:
- Resistance of the potentiometer wire = 10 Ω
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