At what distance of separation, r, must two 3.20 x 10-9 coulomb charges be positioned in order for the repulsive force between them to be 83.4 n?

Explain the doppler effect in terms of frequency, wavelength, and speed.

What are similarities and differences of reflection, refraction, diffraction and absorption?

How are series and parallel circuits simililar? both have multiple paths for electrons to travel. both require resistors in their circuits. both require a switch to complete the circuit. both have at least one path for electrons to travel.