Question

Which of following options is correct for $a,bandc$ ?

• A. $a=$ used for doing mechanical work
  $b=$ chemical energy as plant food
  $c=$ heat energy used for domestic, industrial purposes
• B. $a=$ heat energy used for domestic, industrial purposed
  $b=$ used for, doing mechanical work
  $c=$ chemical energy as plant food
• C. $a=$ chemical energy as plant food
  $b=$ heat energy used for domestic, industrial purposes
  $c=$ used for doing mechanical work
• D. $a=$ heat energy used for domestic, industrial purposes
  $b=$ chemical energy as plant food
  $c=$ used for doing mechanical work

Answer 1

The correct option is C $a=$ chemical energy as plant food

$b=$ heat energy used for domestic, industrial purposes
$c=$ used for doing mechanical work

Plants traps the light energy of the sun and carbon dioxide and converts its into carbohydrates and oxygen. It is a biochemical process. Hence (a) is chemical energy as plant food.

Decay of plant and animals millions of years ago resulted in formation fo fossil fuels. These fuels on combustion produces heat. Hence, (b) is heat energy used for domestic and industrial purposes.

Source of energy for humans and animals to carry out their daily function are plants. Hence (c) is used for mechanical work.