Calculate the amount of energy available to lion in the following
food chain if plants have 20,000 J of energy available from the
sun.
Plant ? Deer ?Lion

Dear Student,

​​​​In an Ecosystem, the transfer of energy in food chain follows the 10%  energy law. According to this law  only 10% of energy is transferred from one trophic level to other, rest of energy is either used by the organism or gets lost in the environment. 

Lets apply this law to the question:-

If 20,000J is the complete amount of energy  available to plants after absorption, then according to energy transfer law, only 10% of it is transferred to next trophic level.

So, 10% of 20,000 is  2000J, which is transferred to the deer.

Similarly 10% of Deer's energy(2000J) is transferred to lions which is only 200J.

Result- The amount of energy transferred to lion is 200J.

​​​​​​​Regards.