Question

the second law of thermodynamics tells us that when energy changes forms, what happens? it increases with each transformation. some of it is lost, usually as heat. it is created out of nothing.

Explanation:

The second law of thermodynamics states that energy conversions are not 100% efficient; usable energy decreases as some is dissipated, typically as thermal energy (heat), increasing the system's entropy. The other options violate thermodynamic laws: energy cannot be created (violates first law) nor increase in usable form during transformation.

Answer:

Some of it is lost, usually as heat.