Mechanical Engineering - Engineering Mechanics - Discussion

The law of conservation of energy simply tells that energy in any form can neither be created nor be destroyed. It changes from one form of energy to another form of energy.

It will change by applying force in any direction.

Linear momentum is also a conserved quantity, meaning that if a closed system is not affected by external forces, its total linear momentum cannot change.

In classical mechanics, conservation of linear momentum is implied by Newton's laws; but it also holds in special relativity (with a modified formula) and, with appropriate definitions, a (generalized) linear momentum conservation law holds in electrodynamics, quantum mechanics, quantum field theory, and general relativity.

Law of conservation of energy is first law of thermodynamics where as law of conservation of momentum is Newton's second law and both law are not similar so statement is wrong.

It is true that energy not created nor destroyed transformation of energy from one form to another possible. So given description is wrong.

Answer B is wrong because the given question is Newton second law and not the energy conservation law.

Energy conservation principle is it can't be created nor it can be destroyed we can consider system having heat stored in it now we can remove heat from system and can transfer to heat sink and we can add more to it from heat source into system but we can't destroy heat.

This question states that newton's first law.

Here, there may be variation of air resistance and road evenness for that, it would change its momentum.

Free molecule have different masses & momentum so without acting force.