Question

Each member of a family of 5 persons derived their average energy need of 2700 kcal by consuming goat meat. How much energy of sun had fallen on vegetation for preparing food for the goat ? (Take 1 cal = 4.2 J)
(A) 113.4 × 10⁹ J
(B) 567 × 10⁹ J
(C) 113.4 × 10¹⁰ J
(D) 567 × 10¹⁰ J

Answer 1

Answer:

B is the correct answer I think so

Answer 2

Answer:

Correct answer is:- (B) 567 × 10⁹ J

Explanation:

Total energy consumed by five people :- 5 × 2700 × 1000 × 4.2 = 567 × 10⁵ J

The chain is:- Sun → Plants → goat→ human

Since, plants absorb 1% energy from sun and according to 10% law.

Now energy available to goat = 100 × 567 × 10⁵ / 10 = 567 × 10⁶ J

Similarly, energy available to plants = 100 × 567 × 10⁶ / 10 = 567 × 10⁷ J

Hence, energy in the sun = 100 ×  567 × 10⁷ =  567 × 10⁹J

Hence, the correct option is (B)