what holds the atoms in plastic together

The electric potential a distance r from a small charge is proportional to what power of the distance from the charge? a. r^-1 b. r c. r^-2 d. r^2

You charge a parallel-plate capacitor, remove it from the battery, and prevent the wires connected to the plates from touching each other. when you increase the plate separation, what happens to the following quantities?

What is the name of the perceived change in a sound wave’s frequency due to motion between the observer and the sound source?