First law of thermodynamics is also known as the law of:

1. conservation of mass
2. conservation of energy
3. conservation of force
4. conservation of momentum

Choose the correct statement(s):

A. According to the first law of thermodynamics, when energy is put to work, a part of it is always converted to non-useful form such as heat, mainly due to friction and radiation.

B. According to the second law of thermodynamics, energy can be transformed from one form to another, but it can neither be created nor destroyed.

1. Both (A) and (B)
2. only (B)
3. only (A)
4. None of these

What is a food chain?

State the law which governs the energy flow in an ecosystem.