IIT JEE , AIEEE Forum - Physics , Electricity

rahul1993

what can be the definition of electric potential?

how can we derive the formula for electric potential?

risin

INDIAN_ARMY19890

electric potential at a point can be defined / calculated as / by calculating the amount of work done by external agent against the electrostatic force in carrying a unit +ve charge from very large distance(infinity) to tht point

payal_bon

DEFINITION
Electric potential at a point can be defined as the amount of work done to move a vanishingly small test charge from infinity to that point per unit charge of it.

DERIVATION
T o find the electric potential at P at a distance r from the pt charge q. Let A be an arbitary point on the path joining infinity to the pt P where a vanishingly small test charge dq is kept. Distance of A from q is x and eleectric field at A be E where
E= q/(4piEox^2)

To move the test charge towards q by AB = dx small work done
dW= F.dx
= dqE.dx
= dqEdxcos180
= -dqEdx
[integration sign=int]
[infinity=@]
Total work done W= - int[ (dqE) dx
W/dq = -int Edx
= -int{@ to r} q/(4piEox^2) dx
= -q/(4piEo) int{@to r} x^-2dx
= -q/(4piEo)[ -1/r + 1/@]
W/dq = q/(4piEor)

chinmay_saxena01

payal is absolutely correct,,,

Ask & Discuss Questions with Community & Experts