Title: Website / Electric Field / E&M-EFMS-PT1

Q: Why is charge named after the process of loading (Latin *carricare*)?
Because people observed certain materials becoming [...] with a force after [...].
A: “loaded”; rubbing

Q: Electron is a Greek word meaning  [...]. It was one of the first materials observed to attract light objects when [...].
A: amber; rubbed

Q: State Coulomb’s law in formula form.
A: \( F = k \dfrac{q_1 q_2}{r^2} \)

Q: What does the magnitude of a force vector represent?
The .... of the force.
A: strength

Q: True or False: The direction of the force vector is the direction in which the particle feels the force.
A: True

Q: True or False: If we flip the signs by the operation q → -q, the laws of physics will change.
A: False

Q: The direction of the force vector in Coulomb’s law (between two point charges) is [...].
A: radial

Q: In Coulomb’s law, if I have an object with a non-uniform charge distribution, I can treat it as a point charge at some location.  What do you think?
A: only valid for ideal point charges or under special symmetry (like spherical shells), not in general.

Q: What is the charge of an up quark in units of e? (write the fraction as / eg: +9/8)
A: +2/3

Q: Name at least three elementary particles that have zero electric charge.
A: 1. electron neutrino
2. muon neutrino
3. tau neutrino
4. photon
5. gluon
6. Z boson
7. neutron

A proton is composed of two up quarks with a charge of +2/3 and one down quark with a charge of -1/3, giving a total of +1
Rückseite Extra: Mnemonic: a "pro" gets up twice as hard as he fell down

Q: Quarks are free particles. (True/False)
A: False

Q: In which situation would you prefer to use polar coordinates instead of Cartesian?
A: When the problem has circular or radial symmetry.
When you just want to look smart