-- The apple has heat energy. If its temperature were Absolute Zero,
then the skin on my hand would freeze instantly and fall off.
-- The apple has potential energy, relative to the ground. If I were to
release it out of my hand, gravity would do work on it and pull it with
some speed to the ground, where it would have the kinetic energy to
break some blades of grass and dig a small crater in the soil.
-- The apple has chemical energy which, if I were to expose it to
human digestion and metabolism by eating it, would change to
glucose, soak into my muscles, and make itself available to me
whenever I need vim and vigor, mental alertness, visual acuity,
and the wherewithal to to escape any unexpected beast that might
in turn set upon me with the intention of converting MY entire person
into food energy for its own use.