Why do some physics textbooks say P = dK/dt and others say P = dE/dt?

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SUMMARY

The discussion clarifies the definitions of power (P), kinetic energy (K), and energy (E) in physics. It establishes that P represents power, K denotes kinetic energy, and E refers to total energy, which includes both kinetic and potential energy (U). The formula P = dK/dt is used in contexts where kinetic energy is the focus, while P = dE/dt applies to total energy transfer. The generic definition of power encompasses any energy transfer, including heat transfer, and is expressed as P = dW/dt when work is performed by an external force.

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This discussion is beneficial for physics students, educators, and professionals seeking clarity on the definitions and applications of power and energy in various physical scenarios.

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Homework Statement
I am interested in why some physics textbooks say P = dK/dt (namely morins classical mechanics) while others say that P = dE/dt (namely physics for scientists and engineers with modern physics)
Relevant Equations
P = dK/dt = dE/dt
Are they assuming that E = K in physics for scientists and engineers with modern physics, but I though E = K + U?Many thanks!
 
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What is P, K and E?

Is P power, is K kinetic energy and E is energy, what kind of energy?
 
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malawi_glenn said:
What is P, K and E?

Is P power, is K kinetic energy and E is energy, what kind of energy?
Thanks for your reply @malawi_glenn! Here I'll send you a screen shot what it says.
 
1670133901931.png
 
The text pretty much explains it.

The generic definition of power is ANY energy transfer, like transfer of heat etc.

Then in the case of an external force that is performing work, you will get P = dW/dt
 
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malawi_glenn said:
The text pretty much explains it.

The generic definition of power is ANY energy transfer, like transfer of heat etc.

Then in the case of an external force that is performing work, you will get P = dW/dt
Ok thank you @malawi_glenn!
 

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