Physical interpretation of Force=power/velocity

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The discussion centers on the equation Force = Power/Velocity and its physical interpretation. A constant force requires an increase in power as velocity increases to maintain constant acceleration, contradicting the initial assumption that power decreases with increasing velocity. The relationship between force, mass, and acceleration is clarified, emphasizing that constant force and mass yield constant acceleration. An example involving a glider illustrates how power relates to drag and velocity, showcasing energy transfer dynamics. Overall, the key takeaway is that maintaining constant force necessitates increasing power with speed.
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I understand the derivation of the equation Force=power/velocity, but I'm not sure I quite understand the physical interpretation of this. If you had a constant force acting on a particle in a vacuum, then it would gain velocity and as it did so the power would have to go down for the force to be constant. Since the only transfer of energy is into kinetic energy as the particle is in a vacuum. If the power goes down this means the rate at which it gains kinetic energy decreases. This means its acceleration decreases but that doesn't make sense to me, why given a constant force is acceleration not constant. If you combine it with F=ma this implies that the mass of the particle has to increase for this to be the case. Am I intepreting all this correctly?
 
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The physical interpretation is that to apply a constant force and hence a constant acceleration, you must increase the power as the speed increases.

When you look at force=power/velocity and conclude that as velocity increases power must decrease to keep force constant, you have it backwards - to keep the value constant as the denominator of a fraction increases, you have to increase the numerator as well.
 
Nugatory said:
The physical interpretation is that to apply a constant force and hence a constant acceleration, you must increase the power as the speed increases.

When you look at force=power/velocity and conclude that as velocity increases power must decrease to keep force constant, you have it backwards - to keep the value constant as the denominator of a fraction increases, you have to increase the numerator as well.

Oh dear I feel super dumb now :O

Thank you though :)
 
When the force is constant, if the mass is constant too, the acceleration keeps a constant value, since F=ma...

An example of power, velocity and force with constant velocity/zero acceleration is in the case of a glider moving at constant velocity. The force of drag times velocity is the power of the glider; i.e. power=drag*airspeed... Of course, in this case, the energy of the glider comes from the variation of potential energy, as the glider loses altitude... Also, power=weight of the glider*vertical velocity... The drawing shows the forces and the speeds U,V, WW...
9643819798_5639ebe4e0_n.jpg
 
I have recently been really interested in the derivation of Hamiltons Principle. On my research I found that with the term ##m \cdot \frac{d}{dt} (\frac{dr}{dt} \cdot \delta r) = 0## (1) one may derivate ##\delta \int (T - V) dt = 0## (2). The derivation itself I understood quiet good, but what I don't understand is where the equation (1) came from, because in my research it was just given and not derived from anywhere. Does anybody know where (1) comes from or why from it the...

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