3.2 Electric Charge 🔋

Charge is a fundamental property of subatomic particles. There are 2 types of charges: positive and negative.

A proton has a positive charge, while an electron is negatively charged. The amount of charge on an object can be measured in either Coulombs (C for large amounts of charge or elementary charges (e) for small amounts of charge. If you've taken chemistry already, you've most likely talked about the charge of atoms or ions as 1, 2, etc. ✨ These charges are measured in elementary charges. For this course, most of the time, we'll be dealing with "larger" amounts of charge and will use Coulombs as our primary unit of charge.

Simply put, "likes repel, opposites attract". 2 positive charges will repel each other, and likewise, 2 negative charges repel. Different charges (+ and -) will attract.

Try using the PhET simulation to see how a charged balloon can stick to the sweater as well as to the wall.

A metal paper clip is attracted to a positively charged metal ball ⚽️ . What could be the charge on the paper clip?

Negative or neutral. As long as the ball is positive it will attract either a negatively charged or a neutral object!