What happens to energy as it flows through a food web?

Well , the plants or autotrophs or the producers take 10% of the energy from the sun. And as it is transferred through the food cycle or web..each of the consumers take 10% of the energy present in the previous trophic level. This is the 10% energy law.
Say, for e.g. sun has 10,000 Joules of energy...a plant will take 10% of it..ime 1000 J energy..a grasshopper feeding on the plant will derive 10% of THAT ..i.e 100 Joules of energy so on.

Ithink that its like 15 mph.