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- Questions I came up with after reading Wikipedia's section on the Tsiolkovsky's equation.

It is argued that the correct interpretation of Newton's 2nd Law for one body of mass ##m## reads "The dynamics (i.e. vector sum of all external forces acting on the body = "all its interactions") dictates the kinetics (i.e. time derivative of the momentum vector = "motion")", under the

Now let us assume that the effect of the external forces is to dictate the motion of the body by making it lose mass, i.e. we step out of Newton's 2nd law's assumptions. We are also told that:

##\vec{F}_{\mbox{ext}}(t) = \frac{dm(t)}{dt}\vec{v}(t) + m\frac{d\vec{v}(t)}{dt} ## (1).

I have four questions: does (1) still make sense, i.e. is it correct? Does it imply a new definition of force replacing/enhancing the one from Newton's laws? Can the two terms of the RHS of (1), if the answer to the first question is "yes", be interpreted as forces? If the answer to the 3rd question is "yes", what would they represent physically?

Thank you!

**assumption that the body's mass will not change during the action of the external forces and after that**.Now let us assume that the effect of the external forces is to dictate the motion of the body by making it lose mass, i.e. we step out of Newton's 2nd law's assumptions. We are also told that:

##\vec{F}_{\mbox{ext}}(t) = \frac{dm(t)}{dt}\vec{v}(t) + m\frac{d\vec{v}(t)}{dt} ## (1).

I have four questions: does (1) still make sense, i.e. is it correct? Does it imply a new definition of force replacing/enhancing the one from Newton's laws? Can the two terms of the RHS of (1), if the answer to the first question is "yes", be interpreted as forces? If the answer to the 3rd question is "yes", what would they represent physically?

Thank you!

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