Compare and contrast mechanical energy of a projectile with mechanical energy of a swing

mechanical energy is due to the position and the motion of an object  in a system. A projectile moves in a curve. When the object leaves, it has mostly kinetic energy

Explanation:

On a swing, the ride starts with a push, giving you kinetic energy.

an ion is a charged atom or molecule. it is charged because the number of electrons do not equal the number of protons in the atom or molecule. an atom can acquire a positive charge or a negative charge depending on whether the number of electrons in an atom is greater or less then the number of protons in the atom.