Newton's Second Law and Inertial Frames Of Refence

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Newton's Second Law is applicable only in inertial frames of reference, where the net force equals the rate of change of momentum. The law can be expressed mathematically, and when using the Einstein Summation Convention, it can be reformulated to include a term for changing coordinates. The discussion raises the question of whether Newton's Second Law can be applied in accelerating frames by incorporating the term mva(dea/dt) instead of introducing fictitious forces. This term may represent the fictitious force in non-inertial frames, such as rotating or uniformly accelerating systems. The exploration of this concept suggests a potential alternative approach to understanding forces in non-inertial frames.
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I have a question about Newton's Second Law and Inertial Frames of Refrence. It is canon that Newton's Second Law is only applicable in an inertial frame of refrence. Newton's Second Law is the net force acting on a body is equal to the time rate of change of the body's linear momentum. Expressed mathematically N.S.L is

\sum F = dp/dt = d(mv)/dt = (dm/dt)v + m(dv/dt)

Lets define a general velocity vector using arbitrary coordinates.The Einstein Summation Convention is being used. Let v = vaea
then (dv/dt) = (dva/dt)ea + va(dea/dt). Substituting this into the equation above and factoring one can arrive at

\sum F = [(dm/dt)va + m(dva/dt)]ea + mva(dea/dt).

In regular cartesian coordinates, the last term in zero. My question is, can one apply N.S.L. in an accelerating frame of refrence by adding the last term, mva(dea/dt), instead of adding ficticious forces?
 
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That last term probably is the fictitious force. Try it with a standard non-inertial frame like a rotating or uniformly accelerating system and see.
 
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