Physics 1602 2 Electric charge and electrostatic interactions

• charge and its unique dimension:

  • A particle has a scalar charge.

• F=kqq/Δr: Yes, that’s correct.

• k can be written as $\frac{1}{4\pi {ϵ}_0}$.

  • ${ϵ}_0$ is the permittivity of vacuum.
  • Sorry, I missed the details around this part. (blu3mo)

• Potential energy:

  • Why is it called “acceptable”?
  • The term does not have a negative sign.
    • Well, that makes sense. When U>0, it represents a repulsive force, which is acceptable.
  • evnm (electron Volt nano meter) is a unit for potential.
    • In this unit, 1.44 evnm represents a potential energy of 1.44 ev when the distance is 1 nm.
  • I’m not sure about the meaning of the units in this part, so I need to confirm. (blu3mo)

• Adding forces:

  • You can simply add vectors, that’s true.
    • Actually, this can only be done in electromagnetic (EM) forces. Really? (blu3mo)
    • I feel like I’ve heard this before.
  • You can use a sigma notation, similar to a for loop, to add forces.