JEE MAIN - Physics (2007 - No. 19)
Charges are placed on the vertices of a square as shown. Let $$\overrightarrow E $$ be the electric field and $$V$$ the potential at the center. If the charges on $$A$$ and $$B$$ are interchanged with those on $$D$$ and $$C$$ respectively, then
$$\overrightarrow E $$ changes, $$V$$ remains unchanged
$$\overrightarrow E $$ remains unchanged, $$V$$ changes
both $$\overrightarrow E $$ and $$V$$ change
$$\overrightarrow E $$ and $$V$$ remain unchanged
Vysvetlenie
As shown in the figure, the resultant electric fields before and after interchanging the charges will have the same magnitude, but opposite directions.
Also, the potential will be same in both cases as it is a scalar quantity.
Also, the potential will be same in both cases as it is a scalar quantity.