(7.3) - Electric Fields

Question 1

What is an electric field?

Answer 1

A region in which a charged object will experience a force over a distance

Question 2

Which force has a greater magnitude and why: Electrostatic or Gravitational

Answer 2

Electrostatic due to their charge being much greater than their weight

Question 3

What is the electric field strength

Answer 3

Force per unit positive charge

Question 4

Derive E=V/d using Fd = Qv

Answer 4

1. Fd=Qv
2. EQd=Qv
3. Ed=v
4. E=v/d

Question 5

What is the trajectory of a charged particle entering a uniform electric field at right angles to the field?

Answer 5

The particle follows a parabolic path, similar to projectile motion under gravity.

Question 6

Describe an electric potenital vs distance (E-r) graph

Answer 6

• E = 1 / r^2
• As r increases, E decreases rapidly, but rate of decrease decreases the further you get from the centre of charge
• Hyperbolic

Question 7

Describe an voltage vs distance (V-r) graph

Answer 7

• V = 1 / r
• As r increases V decreases, but rate of decrease decreases the further you get from the centre
• Parabolic

Question 8

What is the area under a E-r graph?

Answer 8

Negative change in V (Voltage)