Question

w Define potential difference and derive the relation v= w/q . Give its units.​

Answer 1

Answer:

Electric potential difference between two points in an electric circuit carrying some current is the work done to move a unit charge from one point to another. Thus, potential difference is the work done per unit charge and is given as V =W/Q

Explanation:

How do I derive V = W/Q?

W = F. r

Since F = QE = QV/r (since E = V/r)

That makes

W = QVr/r =QV

Rearranging

V = W/Q

Where W = work done, Q = charge, F= coulomb force, E = electric field, r = distance, V = electric potential.

Edit :- Note that here I am assuming the simplest case scenario. And I have not written any of those assumptions.

Answer 2

Potential difference is the amount of energy required to carry a charge from a point to another. The S.I. unit of potential difference is V (volt).

• When a steady current is established in a circuit, a positive charge passes through any cross-section of the circuit in a certain time-interval.
• If the work done by the cell in forcing the charge from its negative to the positive electrode, then the potential difference is given by,

        $V = \frac{W}{q}$

• Here, V is the potential difference, W is the work done and q is the charge.
• The S.I. unit of work is Joule (J) and the S.I. unit of charge is Coulomb (C).
• So, the S.I. unit of potential difference is JC⁻¹ or V (volt).