Potential energy is stored energy. An example is the energy available when a mass is elevated above something. If you release it, it will fall down due to gravity, and it can do work as it...
It is the "potential (possibility) to do work". That is to say, if an object is at a certain height, when it falls it can do some work.
yes. For ex. Gravitational potential energy is caused by height.
Yes.
yes it is