Question

In the following food chain, 20J of energy was available to the hawks. How much energy would have been present in the plants?

Plant------Rat------Snakes-----Hawks

Answer 1

*Following the 10% Law,

Energy available for snake - 20×100/10 = 200J

Energy available for Rat -

200×100/10 = 2000J

Energy available for Plant - 200×100/10 = 20000J

Hope this would help......*

Answer 2

Answer:

The energy present in the plants if 20 J was available to the hawks is 20000 J.

Explanation:

Step 1 : State the law of 10% in a food chain.

It states that, in a food chain only 10% of the energy is transferred to the next Tropic level.

Step 2 : Apply the law of 10% of the food chain.

Let y be the total energy from the snake.

10% of y is = 10/100 × y = 0.1y

Therefore the energy transferred to the hawks is 0.1 y.

Now :

0.1y = 20 J

y = 20/0.1 = 200 J

200 J is energy from the Snakes.

We follow this 10% rule until we reach the plants.

Energy from the rats = 200/0.1 = 2000 J

Energy from the plants = 2000/0.1 = 20000 J