Electric Fields

Question 1

Define electrical field strength

Answer 1

Force per unit charge on a positive test charge placed at that point in the electrical field

EFS = -ΔV/Δx

Question 2

Direction of electrical field

Answer 2

Showing the direction of a positive charged object attracted to a negative side/terminal

Question 3

How to find the electrical field between two parallel plates?

Answer 3

E = V/d

Question 4

Factors that affect the strength of an electrical field

Answer 4

The charge of the body
Concentration of the charge on the surface of the body (Smaller SA = greater E Field)

E = Q/Aε

Question 5

Definition of Electrical Potential

Answer 5

The work done per unit positive charge on a positive test charge when it is moved from infinity to that position

Positive charge = always positive potential

Negative charge = always negative potential

Electrical Potential = VQ

Question 6

Definition of potential gradient

Answer 6

Change of potential per unit change of distance in any direction

Question 7

What are the equipotentials like between non-uniform and uniform fields?

Answer 7

Non uniform: The closer the equipotentials the greater potential gradient

Uniform: Equipotentials are equally spaced so the gradient is constant

Question 8

What is Coulomb’s Law?

Answer 8

Electric Force between two objects is inversely proportional to the distance^2

Positive force = repulsion
Negative force = attraction

Question 9

Why is E = 0 inside a charged sphere

Answer 9

As E=kQ/r^2, r = 0 inside a charged sphere so E = 0