Electrostatics Basics
Introduction
Electrostatics is a study of charge at rest.
- What you need to remember is that this is all about the electron!
- You must remember that the charge of a single electron is -1,6 x 10-19C.
- You must also remember that the charge of a single proton is +1,6 x 10-19C.
- All other objects become charged because of having extra or lesser electrons than protons.
- You should think of charge as "weight". If the object is "charge heavy" it must have a lot of extra electrons!
- If an objects charge is -1,6 x 10-19C then it has only ONE EXTRA electron.
- If an objects charge is anything else such as, -5 x 10-15C then it obviously has a lot of extra electrons.
What are the things you need to learn?
- Charge of one electron is Q = -1,6 x 10-19C
- Charge of one proton is Q = +1,6 x 10-19C
- How to work out new charges when charged objects make contact with each other.
- Like charges repel, and unlike charges attract.
- Use Coulombs Law to calculate the magnitude of these forces.
- Draw Electric Field patterns.
- Calculate Electric Field strengths.
- Calculate Electrical Potential Energy.
Prefixes
Since this section is full of all these small awkward numbers, prefixes are used where possible to represent the x 10power.
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Example 1
5 x 10-6C can be written as 5uC (pronounced microcoulombs)
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Example 2
-3 x 10-9C can be written as -3nC (pronounced nanocoulombs)
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Example 3
8 x 10-3C can be written as 8mC (pronounced millicoulombs)
You will pick up a few more as we go along.
So you must become very good with your calculator! Get to know how to use your calculator by practicising a lot.