Mechanical Engineering - Engineering Mechanics - Discussion

That question is based on newton 1st law of motion. According to this law, every body that time up to not motion then not external force are applied.

Energy conservation should not be confused with linear momentum. Whilst one concerns itself with the fact that energy cannot be created or lost, the other is focused on changes that can happen within a system of masses moving in a particular direction when external forces are applied. Is there a change in system energy when momentum changes? Possibly.

Kinetic energy of a moving system of masses is 0.5 x (m1 x v1^2 + m2 x v2^2 x ......mn x vn^2). The mass of objects will not change unless some molecular distortion occurs which is not treated herein. However, the velocity can reduce or increase.

Hence, the system energy can go up or go down. However, if this is happening in a closed system, the kinetic energy lost becomes gained as heat energy. Hence, total energy remains unchanged. But if this is not a closed system, then energy is exchanged across our artificial boundary which contains the system of masses, and therefore system energy changes.

So, the key word here for the statement to be true is whether the system is CLOSED or OPEN. And, since we were not informed on this, the assumption is that it is an OPEN system in which case the correct answer is FALSE because the energy conservation principle will NOT hold in an OPEN system.

According to conservation of energy principle. Energy can neither be created nor be destroyed. It can only be transferred from one form to another.

According to conservation of energy principle. Energy cannot be created nor be destroyed. It can only be transferred from one source to another.

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.

It's all about law of conservation of energy.

Principle of conservation of energy states that energy can neither be created nor destroyed. In another approach it can be stated as "the total energy of an isolated system remains constant.

The force applied should be an external 'unbalanced' force in that direction.

Momentum doesn't need constant force, if a body is accelerating in a direction then there must be a constant force applied on it, also the question is asking about SYSTEM OF MASSES, of which momentum can be changed in a by applying force in any direction & not in particularly that direction.

If a body has some constant momentum in one direction, it means that a constant external force is acting on it. But if the momentum has to change in magnitude in that direction then an external unbalanced force has to act.

Here only external force is given and not external unbalanced force hence answer is false.