PHYS 2002 Lecture : 2002 Lecture 1
Document Summary
We never said what mass is, only how it behaves. This semester, we are concerned with something called charge. *and just like in mechanics, e&m will not tell us what charge is, but only how it behaves. Like mass, charge is an intrinsic property of matter, and it comes in 2 types: *the si unit of charge is the coulomb [c]. Proton charge is positive: +1e = +1. 602 10-19 c. Electron charge is negative: -1e = -1. 602 10-19 c. *in nature, atoms like to have equal numbers of protons and electrons, so that their net charge is zero. Electrical charges can be transferred between different objects. For example: if we remove an electron from a neutral atom, we are left with a positively charged ion. We can transfer electrons between to objects by touching them together: Hard rubber / animal fur electrons are transferred from the fur to the rod. The rod becomes negatively charged, and the fur positively charged.
