Electric Field

Question 1

Coulomb’s Law

Answer 1

Coulomb’s Law states that the magnitude of the electric force F, between two point charges Q1 and Q2 is proportional to their charges and inversely proportional to the square of their separation, r.
F = k (Qq / r²)
k is 4piE

Question 2

Define electric field

Answer 2

An electric field is a region of space where a charge placed in that region experiences an electric force.

Question 3

Define electric field strength

Answer 3

The electric field strength at a point is defined as the electric force exerted per unit positive charge acting on a test charge place at that point.
E = F/q

Question 4

Define electric potential energy

Answer 4

Electric potential energy is the work done by an external agent in bringing the charge from infinity to that point.

Question 5

Define electric potential

Answer 5

Electric potential is the work done per unit positive charge in bringing a small test charge from infinity to that point by an external agent.
V = U / q

Question 6

Define equipotential lines

Answer 6

Equipotential lines are lines that join points with the same potential and are perpendicular to electric field lines.
Movement along equipotential line requires no work and no change in electric potential between any two points.

Question 7

Define uniform electric field

Answer 7

A uniform electric field is a region with which:
1. the electric field strength at any point has the same magnitude and direction.
2. the electric field lines are parallel and equally spaced and directed from higher to lower potential.