Relate energy conversion to the law of conservation of energy.

Energy remain conserved while converting its form from one to another

Explanation:

As per the conservation of energy, energy always changes its form from one form to another and it is neither destroyed nor created. The total amount of energy always remains the same.

There are several forms of energy such as thermal energy, electrical energy, nuclear energy, electromagnetic energy, etc.

For example –  

During any chemical reaction, form of one chemical changes into another. In this process some amount of chemical energy remains conserved while the deficit in total starting energy is released as heat and light energy  

measure their densities same density, same sub

measuring things 1 litre of water