1). Nuclear energy is released when the nucleii (nucleuses) of atoms
either split up into smaller pieces, or else small nucleii join together
to make bigger ones.
Light ... and all other forms of electromagnetic energy ... comes out of
atoms when their electrons fall toward the nucleus, from bigger orbits to
smaller orbits.
2). Energy conversion: Turn on a flashlight.
Chemical energy stored in the battery converts to electrical energy
when it leaves the battery. Then the electrical energy flows through
the little bulb, and gets converted into light and heat energy.
3). The energy conversion in a light bulb produces some of the kind
you want ... the light ... and also some of the kind that you don't want ...
the heat.
You can also use a small light bulb as a heater, like to keep your hamster's
cage warm at night. If you do that, then the energy conversion in a light bulb
produces some of the kind you want ... the heat ... and also some of the kind
that you don't want ... the light.
4). You can move parts of your body because of energy from the sun.
Electromagnetic energy in sunshine ===>
is absorbed by green leaves, and
converted to chemical energy in the plant ===>
you eat the plant,
the chemical energy is stored in your body fat ===>
you work out at the gym
the fat in your body is used to move your muscles
and is converted to kinetic energy to run on the treadmill.