Question

Define electric potential between two points in an electric field derive an expression for it

Answer 1

The difference in the electric potential of two different points is known as potential difference.

Here, electric potential is defined as the work done in moving a unit positive charge from one point to another.

The unit of electric potential and of potential difference (also known as Voltage) is Volts, denoted by the letter V.

Potential difference is also written as p.d. or V.

From the definition, we get

V = W/Q

or

Q = W/V

or

W = V*Q

The above three expressions represent an expression for p.d.

If any of the two quantities are known, the third one can be calculated using the above three formulas.

For example,

Q. Calculate the potential difference across two points if charge moved is 10 C and the work done is 20 J.

Ans. Using the formula V = W/Q,

we get

V = 20 / 10

V = 2 Volts