# 6.2 Electric Fields Flashcards Preview

## Physics A Level > 6.2 Electric Fields > Flashcards

Flashcards in 6.2 Electric Fields Deck (15)
1
Q

Why do electric fields exist?

A

Due to charged particles

2
Q

How are uniformly charged spheres modelled?

A

As a point charge at its centre

3
Q

How do electric field lines represent electric fields? (3)

A

The arrow shows the direction that a point positive charge moves
At right angles to the surface of a conductor
Separation represents electric field strength

4
Q

How is a uniform electric field represented?

A

Equally spaced, parallel lines

5
Q

Define electric field strength

A

The force experienced per unit positive charge at a point in an electric field

6
Q

State Coulomb’s law

A

The force between two point charges is directly proportional to the products of the charges and inversely proportional to the square of their separation

7
Q

What are the similarities between gravitational fields and electric fields? (2)

A

Point masses/charges produce a radial field

Field strength is force per unit mass/positive charge

8
Q

What is the difference between gravitational fields and electric fields?

A

Masses always produce an attractive field whereas charges produce both attractive and repulsive fields

9
Q

What does the capacitance of a parallel plate capacitor depend on? (3)

A

Separation between the plates
Area of overlap between the plates
The dielectric used between the plates

10
Q

How does a charged particle move in an electric field? (3)

A

A charged particle moves away from the plate of the same charge
It experiences a constant electrostatic force, giving it constant acceleration
A particle moving at right angles to the field behaves similarly to a projectile, with constant vertical acceleration and constant horizontal velocity

11
Q

Define electric potential

A

The work done in bringing a unit positive charge from infinity to that point in an electric field

12
Q

When is electric potential zero?

A

At infinity

13
Q

Define electric potential difference

A

The work done per unit charge between two points around a particle of charge

14
Q

What is an equipotential?

A

A line or surface along which the electric potential is the same

15
Q

What does the area under a force-distance graph represent?

A

Work done