Question on Newton's first law

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An object with no resultant force can maintain a constant velocity due to Newton's First Law of Motion, which states that an object in motion will stay in motion unless acted upon by a net force. This principle indicates that to change an object's speed, a force must be applied, whether to accelerate or decelerate. The discussion highlights that while kinetic energy and momentum are related to motion, they do not necessitate a continuous application of force to maintain constant velocity. Misconceptions often arise from everyday experiences where friction and air resistance obscure these fundamental laws. Ultimately, understanding these concepts clarifies that constant motion does not require ongoing force.
Lim Y K
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An object with no resultant force can still be moving at constant velocity. Why? Is it because of its kinetic energy or has it got nothing to do with energy?
 
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Lim Y K said:
An object with no resultant force can still be moving at constant velocity. Why? Is it because of its kinetic energy or has it got nothing to do with energy?
An object which is moving which also has no net force acting on it continues to move without change in its motion. That's Newton's First Law of Motion.

If you want to make an object go slower, you must apply some force to it.
If you want to make an object go faster, you must apply some force to it.
If you want the motion of the object to stay the same, don't apply any force to it.

Newton's First Law is not concerned with how the motion of the object started initially, only what happens to the object while it is in motion (or not, as the case may be).
 
Lim Y K said:
Is it because of its kinetic energy or has it got nothing to do with energy?

In addition to SteamKing's answer: It is because of its momentum but it has also to do with energy. Changing the speed changes momentum and kinetic energy and both require a force.
 
Common sense and intuition can be deceptive. In everyday experience a constant force may seem to be needed to keep an object moving. However, Galileo discovered that friction and air resistance were obscuring underlying laws. Galileo is quoted verbatim in Newton's First Law.
 

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