If `vec(E )` equals zero at a given point mus V equal for that point .

Explanation

To answer the question, "If \( \vec{E} = 0 \) at a given point, must \( V \) equal for that point?", we can follow these steps:

### Step 1: Understand the relationship between electric field and potential
The electric field \( \vec{E} \) is related to the electric potential \( V \) by the equation:
\[ \vec{E} = -\frac{dV}{dr} \]
This means that the electric field is the negative gradient of the electric potential.
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