Why there is no force acting in an object with constant velocity?

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An object moving at constant velocity experiences no net force, meaning the forces acting on it are balanced. For example, when riding a bicycle, pedaling generates a force that counters resistive forces like wind and friction. If these forces are equal, the bicycle maintains its speed without accelerating or decelerating. This concept aligns with Newton's first law, which states that an object in motion will remain in motion unless acted upon by a net external force. Understanding that constant velocity implies zero net force is crucial for grasping basic mechanics.
abi.ayan
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According to my level of knowledge,my point of view regarding an object moving with constant velocity is that there should be a force acting on it for its continuous motion(eg:when riding bicycle we give a force continuously).But the theory says it is not.can anyone explain?
 
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On a bicycle, if you stop pedaling, you don't immediately stop. You keep moving with the same velocity you had just before you stopped pedaling, and then you gradually slow down. Slowing down is due to forces acting on your bicycle--wind resistance, friction in the wheels, etc. But if there were no force acting on your bicycle to slow you down, you would continue to coast at a constant velocity once you stop pedaling. But since there are forces acting to slow you down such as wind resistance, maintaining a constant speed requires you to pedal just enough to cancel the resistance force--when one force cancels the other, you are left with zero net force and thus remain at a constant velocity.
 
But there are forces acting on a material point moving with constant velocity. It's just that their resultant is 0. The second postulate of mechanics only speaks about the resultant force, not on individual components.
 
Jolb said:
On a bicycle, if you stop pedaling, you don't immediately stop. You keep moving with the same velocity you had just before you stopped pedaling, and then you gradually slow down. Slowing down is due to forces acting on your bicycle--wind resistance, friction in the wheels, etc. But if there were no force acting on your bicycle to slow you down, you would continue to coast at a constant velocity once you stop pedaling. But since there are forces acting to slow you down such as wind resistance, maintaining a constant speed requires you to pedal just enough to cancel the resistance force--when one force cancels the other, you are left with zero net force and thus remain at a constant velocity.

So the bicycle doesn't move due the force given by me.But the force I gave only cancel out the air resistant and frictonal force.I am I right?
 
abi.ayan said:
So the bicycle doesn't move due the force given by me.But the force I gave only cancel out the air resistant and frictonal force.I am I right?

That's correct. Velocity is not related to currently acting forces. Only acceleration is related to currently acting forces. constant velocity = no acceleration = sum of forces is zero.
 
A.T.
Obviously I need more clarity to understand that one

Dave
 
For simple comparison, I think the same thought process can be followed as a block slides down a hill, - for block down hill, simple starting PE of mgh to final max KE 0.5mv^2 - comparing PE1 to max KE2 would result in finding the work friction did through the process. efficiency is just 100*KE2/PE1. If a mousetrap car travels along a flat surface, a starting PE of 0.5 k th^2 can be measured and maximum velocity of the car can also be measured. If energy efficiency is defined by...

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