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Rain derops each of mass m falling from ...

Rain derops each of mass m falling from rest in air experience an upward force given by f= - bv where b is a constant and v is velocity of the drop. Using work energy theorem, derive an expression for
(A) `v=f(t)` i.e. velocity function of time.
(B) `(dE)/(dt)=f(t)` where E = Total machanical energy of the rain drop
( C) Draw the graphs `(dE)/(dt.(dU)/(dt) and P_("viscous")` as a function of time U is potential energy and P represent power ?

Text Solution

Verified by Experts

`(A)v=(mg)/(b)(1-e^((-bt)/(m))),(b)(dE)/(dt)=(m^(2)g^(2))/(b)(1+e^((-bt)/(m)))`
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