Electric Fields Flashcards
How are electric fields shown in physics?
They are shown with field lines, which are just lines with arrows. The arrows always go from positive to negative, so they go out of our positive particle but into our negative particle.
You must draw them at right angles to the surface. When you are asked to draw these field lines in an exam, make sure to show a fair few, around 8 of them.
Where is the electric field strongest?
The field is strongest closer to the particle. It gets weaker the further away you get.
As charged particles get closer together, their electric fields will start to interact more and more.
What is an electrostatic force?
When 2 oppositely charged particles’ electric fields interact, there will be an attractive force between them. This is called an electrostatic force, or electrostatic attraction.
True or False?
When 2 particles of the same charges’ electric fields interact, they would have an attractive force between them.
False
When 2 particles of the same charges’ electric fields interact, they would repel each other, similar to magnets. This is because like charges repel.
What is the process of ionisation?
If you had an object that was really strongly charged, like a piece of metal for example, it would have a strong electric field all around it. Whereas the nearby air particles would have no charge.
In this state, air is an electrical insulator and cannot conduct electricity. However, in some cases, a strong electric field can cause the surrounding air particles to lose electrons and become positive ions. This process is called ionisation.
Once air has become ionised, it is able to conduct electricity. This is how sparks are able to travel between objects.
