Problem with Newtons second law

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Newton's second law can be expressed as F = m*dv/dt + v*dm/dt, where the first term represents acceleration due to applied force and the second term accounts for changes in mass. In non-relativistic scenarios, the applied force does not change the object's mass, making the second term effectively zero. The equation serves as a definition of force based on observable effects, rather than a direct explanation of how forces operate. Some discussions suggest that F = ma is a more straightforward definition of force. Understanding these nuances clarifies the relationship between force, mass, and acceleration.
Physonic
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hello!

here's my problem:
Newtons second law implies: F=m*dv/dt+v*dm/dt
first part of the equation says if I act on the object then it's reaction will be acceleration, but the second part says if act on the object it will cause changes in object's mass.
In case where I'm dealing with non relativistic case how applied force can change object's mass?

thank you!
 
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In the non-relativistic case the applied force doesn't change the object's mass, so the second term is zero.
 
A practical example is how the mass of a vehicle decreases as fuel is burnt.
 
Physonic said:
here's my problem:
Newtons second law implies: F=m*dv/dt+v*dm/dt
first part of the equation says if I act on the object then it's reaction will be acceleration, but the second part says if act on the object it will cause changes in object's mass.
In case where I'm dealing with non relativistic case how applied force can change object's mass?
It's the other way around. F=dp/dt=m*dv/dt+v*dm/dt is one definition of force. This equation is not saying what forces do, it is giving a definition of what a force is in terms of observable effects. Both of those terms on the right hand side are observable effects. There are other definitions of force, by the way. Some prefer F=ma as definitional, for example.
 
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