Power associated with net force

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REVIANNA
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Homework Statement



How to prove :
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##P*F_net=((dK)/(dt))##
i.e. power associated with the net force is the rate of change of kinetic energy.

The Attempt at a Solution


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if I use the definition of power ans then that of work I get (m*a*ΔS )*(F_net)
further using F_net=ma
LHS= ##m^2*a^2*ΔS##

There is no question along with it for which I could have though about the system and forces.
so I am assuming const force and acceleration.
 
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REVIANNA said:
P∗Fnet=((dK)/(dt))P*F_net=((dK)/(dt))
Is that product of force and power on LHS? If yes, the equation looks dimensionally incorrect.
Actually, if you solved dK/dt first, you'll get power.
 
Last edited:
cnh1995 said:
Is that product of force and power on LHS? If yes, the equation looks dimensionally incorrect.
Actually, if you solved dK/dt first, you'll get power.

so sorry ,actually the F_net was written as the subscript P ,not their product
this makes complete sense now
##P_F=(dK/dt)##
 
REVIANNA said:
so sorry ,actually the F_net was written as the subscript P which not their product
this makes complete sense now
##P_F=(dK/dt)##
Then I believe answer is a couple of steps away. Good luck..
 
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