# Electricity

HideShow resource information
• Created by: LZ95
• Created on: 02-04-14 16:11
What is the definition of electric field strength?
The electric field strength (E) at a point in the field is defined as the force per unit charge on a positive test charge placed at that point.
1 of 13
What is the difference between conductors and insulators?
Conductors contain a lot of free electrons; insulators don't.
2 of 13
Name 3 facts about the electric field lines between two oppositely charged parallel conductors
The electric field lines are: 1. Parallel to each other; 2. At right angles to the plates; 3. From the positive to the negative plate.
3 of 13
What is the definition of electric potential?
Work done per unit positive charge on a small positively charged object when it is moved from infinity to that position
4 of 13
What are equipotentials?
Lines of constant potential
5 of 13
If a test charge was moving along an equipotential, would work be done on it? Why/why not?
No work would be done because the force due to the field is at right angles to the equipotentials which means the field lines cross equipotentials are right angles.
6 of 13
In which way does the potential gradient increase?
In the opposite direction to that of the electric field.
7 of 13
Whats is Coulomb's law?
Force is proportional to 1/r^2
8 of 13
What is a point charge?
A charged object in a situation where distances under consideration are much greater than the size of the object
9 of 13
What is a test charge?
A charge in an electric field that is a point charge which does not alter the electric field which it is placed in.
10 of 13
What is the general rule for the resultant electric field strength?
It is the vector sum of the individual electric field strengths
11 of 13
Name 3 similarities between gravitational force and electric force
Both proportional to 1/r^2; gravitational potential is energy per unit mass and electric potential is energy per unit + charge; g is the same everywhere and E is the same everywhere
12 of 13
Name 3 differences between gravitational force and electric force
Gravitational force is between two masses whereas electric force is between two charged objects; g-force attracts only whereas e-force repels as well, constant of proportionality is different
13 of 13

## Other cards in this set

### Card 2

#### Front

What is the difference between conductors and insulators?

#### Back

Conductors contain a lot of free electrons; insulators don't.

### Card 3

#### Front

Name 3 facts about the electric field lines between two oppositely charged parallel conductors

### Card 4

#### Front

What is the definition of electric potential?

### Card 5

#### Front

What are equipotentials?

## Comments

No comments have yet been made

## Similar Physics resources:

See all Physics resources »See all Electric fields resources »