Chapter 22 - Electrical Fields

Question 1

What is an electrostatic field?

Answer 1

An electrostatic field is a region of space surrounding a charged body, in which another charged body will experience an electrostatic force

Question 2

What are the two types of electrical fields?

Answer 2

E-fields that have constant uniform strength
E-fields that are radial and so strength decays as the square of displacement from the centre of mass of charged body increases

Question 3

What is electrostatic field strength?

Answer 3

The force per unit charge exerted on a positive body at a point in the e-field

Question 4

What is the simple formula for electrostatic field strength?

Answer 4

E = F / Q

Question 5

Why do electrostatic fields arise?

Answer 5

Due to a potential difference between two points in space

Question 6

What is Coulomb’s law?

Answer 6

The electrical force between two charged points:
Either attractive or repulsive
Proportional to the product of their charges
Inversely proportional to the square of distance between the CoM of both bodies

Question 7

What is Coulomb’s formula for electrostatic force?

Answer 7

F = Q₁ * Q₂ / 4 * pi * E₀ * r ²

Question 8

What is the value of E₀?

Answer 8

8.85 x 10^-12

Question 9

What is the formula for electrical field strength using Coulomb’s laws?

Answer 9

E = Q / 4 * pi * E₀ * r²

Question 10

Under what condition is electrostatic force around a sphere radial?

Answer 10

The distance from the sphere of the charged body is greater than the radius of the sphere

Question 11

What is the formula for electric field strength using distance?

Answer 11

E = V / d

Question 12

What is the formula for electrical energy using Coulomb’s laws?

Answer 12

Energy = Q * q / 4 * pi * E₀ * r

Question 13

What is the formula of voltage in an electrical field?

Answer 13

Voltage = Q / 4 * pi * E₀ * r