electric fields

Question 1

coulombs law

Answer 1

states that the electric force acting between any two point charges is directly
proportional to the product of the charges and inversely proportional to the square of their distance
apart

direction of the force is along the line joining the two point charges in free space

Question 2

electric field strength E

Answer 2

at a point is defined as the electric force exerted per unit positive charge
on a small stationary test charge placed at that point in the electric field

Question 3

equation linking e field strength, e forca and charge

Answer 3

E = F/q

E is electric field strength
F is electric force experienced by charge q

Question 4

why is E = 0 in conductor?

Answer 4

As the charges in the sphere are mobile, they repel one another and move furthest apart and hence will reside on the surface.

for there to be no net movement of charge in the sphere (electrostatic equilibrium), this will mean that the electric field inside the conductor is zero.

having an electric field will cause the charges to move either in or against the direction of the field - > not in electrostatic equilibrium