Electrostatic Potential And Capacitance

Question 1

What is electrostatic potential energy in terms of an external force?

Answer 1

The work done by an external force in bringing a charge from point R to point P against the electrostatic field.

Question 2

What is electric potential?

Answer 2

Electrostatic potential at a point in space is the amount of work done in bringing a unit positive charge from infinity to that point in electric field, without any acceleration. It is a scalar quantity and is denoted by V

Question 3

What is electric potential energy dependent on?

Answer 3

Only on the initial and final positions, not the path.

Question 4

What is the cosine rule used for deriving Electric Potential due to Dipole?

Answer 4

Cosθ = b ²+c ²-a ²/2bc

Question 5

Electrostatic potential difference

Answer 5

the amount of work done in moving a unit positive charge from one point to another it represents the difference in electrostatic potential between the two points and is a scalar quantity

ΔV = VB - VA = WAB / Q

Question 6

What is negative potential difference

Answer 6

Negative potential difference is when the field does the work

Question 7

What is positive potential difference?

Answer 7

Positive potential difference is when work is done against the field

Question 9

Points for Equipotential surface

Answer 9

1. No work is done when the charge moves along the equipotential surface because potential difference is zero.
   2.Equipotential surfaces are perpendicular to the field lines because if not, then work will be done
2. Shape depends on Charge Distribution.

Question 10

How are equipotential surfaces for point charges?

Answer 10

Concentric spheres around the charge

Question 11

How are equipotential surfaces for uniform electric field?

Answer 11

Parallel planes

Question 12

Electrostatic of conductors

Answer 12

(i) The electric field is zero everywhere inside the conductors in an electrostatic equilibrium.
(ii) Electric field just outside a conductor is perpendicular to the surface of the conductor at every point.
(iii) The net charge inside the conductor is zero.
(iv) The electrostatic potential is constant throughout the volume of the conductor and has the same value on its surface.
(v) Electric field at the surface of a charged conductor is E⇀ = σ/ ε₀ n̂
(vi) the surface charge density of charge is different at different points of an irregularly shaped conductor