MCQ
In a region of constant potential:
- AThe electric field is uniform.
- BThe electric field is zero.
- CThere can be no charge inside the region.
- DThe electric field shall necessarily change if a charge is placed outside the region.
✓
Answer
- The electric field is zero.
- There can be no charge inside the region.
We know, the electric field intensity E and electric potential V are dV related as $\text{E}=-\frac{\text{dV}}{\text{dr}}$
or we can write $|\text{E}|=-\frac{\Delta\text{V}}{\Delta\text{r}}$
The electric field intensity E and electric potential V are related as E = 0 and for V = constant, $\frac{\text{dV}}{\text{dr}}=0$ this imply that electric field intensity E = 0.
If some charge is present inside the region then electric field cannot be zero at that region, for this V = constant is not valid.
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