The adjoining figure shows the lines of constant potential in a region in which an electric field is present. The value of potentials are shown. At which of the points A, B and C is the magnitude of the electric field the greatest?

Explanation

To determine at which point (A, B, or C) the magnitude of the electric field is greatest, we can follow these steps:

### Step 1: Understand the relationship between electric field and potential
The electric field (E) is related to the change in electric potential (V) by the formula:
\[ E = -\frac{dV}{dr} \]
This means that the electric field is greatest where the change in potential (dV) is the largest over the smallest distance (dr).

### Step 2: Analyze the equipotential lines
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