The e.m.f. of a primary cell is 2V, when it is shorted then it gives a current of 4A. Calculate internal resistance of primary cell.

Explanation

To find the internal resistance of the primary cell, we can use the relationship between electromotive force (e.m.f.), current, and internal resistance. Here’s the step-by-step solution:

### Step 1: Understand the given values
- The e.m.f. (Electromotive Force) of the primary cell, \( E = 2 \, \text{V} \)
- The current when the cell is shorted, \( I = 4 \, \text{A} \)

### Step 2: Use the formula for e.m.f.
The formula relating e.m.f., current, internal resistance, and terminal voltage is given by:
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