Wattage delivered using triple integral help

AI Thread Summary
The discussion centers on calculating wattage using a triple integral approach, with the equation for instantaneous power given as p(t) = (V^2(t))/R. The user attempts to derive this using a triple integral but receives feedback that the method may be incorrect, suggesting that the integral should be simpler if resistance (R) is constant. Clarifications are made regarding the definitions of average versus instantaneous power, emphasizing that average power requires integration over time. The conversation highlights confusion about the application of integrals in this context and the necessity of understanding varying versus constant resistance. Ultimately, the accuracy of the calculations and the method used are questioned, indicating a need for further review of the concepts involved.
Petyab
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Useful equation.

Avg. Power
p(t)=(V^2(t))/R

My attempt at instantaneous power was

p(t,V,R)= ∫(0->1 for t ∫0->5 for V and ∫0->.1 for R V^2(t)/RdvdRdt

Integrating I go the triple integral of V^3t^2/6R^2

Substituting my values in gave a wattage of 1,250 watts/m^2 at t=1 second, v=5 volts, and R=1 ohms

Using Ohms Law V=IR or I=V/R I calculate now as I write this a current of
I=5/.1=50 amps

Is this correct?
 
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I do not know where you came up with the triple integral thing...you need to review this concept.

If anything, it should be the integral of V/R.

Is your R really varying? If not, it would simply be the integral of V

By the way, p(t) = (v(t))^2 / R is not average power, it is instantaneous power

The average power would by the integral of the instantaneous power over a period of time divided by that amount of time.
 
If R was varying would I be right for instantaneous power? The triple integral follows the rules for setting a triple integral in relation to the variable. The values given are set for R being constant though they should be the same in that case.
 
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