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Raja99
Pl help
\[pl derive the Eq.m v^{'}=mg-b v^{2}\]
Looks like: Net force = force of gravity - air drag Net force from Newton's 2nd law is mass (\(m\)) times acceleration, and acceleration may be written as derivative of velocity (\(v'\)). Force of gravity near Earth is mass times the standard gravity (\(g \approx 9.81\)). And a simple drag model is to say that it is proportional to the square of the speed (\(v^2\)) with some proportionality constant (\(b\)).