The work done to move a unit charge along an equipotential surface from P to Q

Question

The work done to move a unit charge along an equipotential surface from P to Q (A) must be defined as -∫ limitsPQ vecE . dl (B) is zero (C) can have a non-zero value (D) both (a) and (b) are correct

Tardigrade Admin · Accepted Answer

Work done to move a unit charge along an equipotential surface from P to Q, W= -∫ limitsPQ vecE . dl On equipotential surface vecE ⊥ d vecl W =- ∫ limitsPQ E(dl)cos 90°=0

Q. The work done to move a unit charge along an equipotential surface from $P$ to $Q$

must be defined as $- P \int Q E . d l$

is zero

can have a non-zero value

both $(a)$ and $(b)$ are correct

Work done to move a unit charge along an equipotential surface from $P$ to $Q$ ,
$W = - P \int Q E . d l$
On equipotential surface $E ⊥ d l$
$W = - P \int Q E (d l) cos 9 0^{\circ} = 0$

Q. The work done to move a unit charge along an equipotential surface from P to Q

must be defined as −P∫Q​E.dl