Interpreting J/s and J/(s^2): Watts & More

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The discussion clarifies the interpretation of the units J/s and J/(s^2), establishing that J/s is equivalent to Watts, while J/(s^2) represents the rate of change of power over time, or Watts per second. Claude provides a practical example involving a power transmission shaft in a car, where the power transmitted can be calculated using the formula Ẇsh = 2πṅT. The conversation emphasizes that J/(s^2) can be understood as the rate at which power changes when considering non-uniform rotational speeds.

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Just trying to interpret some units here. If J/s is Watt, what does J/(s^2) tell me?
 
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W/s is the rate at which power increases. I can't think of an example of where this unit might be commonly used.

Claude.
 
Something's power is increasing by 1 J/s every second.
 
It is the rate at which power is used, as other have said before me. A practical example, you have a power transmission shaft of a car with an applied torque T, with a constant rotational speed, n. You want to determine the power transmitted to the shaft. Then you will have
\dot{W_{sh}} = 2 \pi \dot{n} T

Edit: Oh, I see you said watts/second. Forget what I said above. That would be the rate of the rate at which power is being used. Well, you could change my n dot to an n double dot, where the n double dot is the rotational acceleration I guess. But I can't see any purpose for doing so. I guess you could interpret it as the rate at which the power being transmitted through the shaft is changing with respect to time, if it has a nonuniform speed, n. If you know n double dot, you can integrate to find the power transmission from t_0 to t_1

\dot{W_{sh}} = \int^{t_1}_{t_0} \ddot{W_{sh}} dt = \int^{t_1}_{t_0}2 \pi \ddot{n} T dt
 
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