How Does Power Calculation Translate to Energy Absorption in a Circuit?

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The discussion revolves around calculating power and energy in a circuit with defined voltage and current functions. The power delivered by the circuit element is calculated as 50 sin(t) cos(t) [W]. To find the energy absorbed over the interval from t = 0 to t = 1 second, integration of the power function over that time frame is required. Participants express confusion about integrating sine and cosine functions and seek clarification on the integration process. The conversation emphasizes the importance of understanding the relationship between power delivery and energy absorption in circuit analysis.
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1. A circuit element is shown below, with the voltage v(t) and the current i(t) defined. The
voltage and current are given as
v (t ) = 5sin (t ) [V]
i (t ) = −10cos (t ) [A] .
Calculate the power that the element is delivering.

b) For the same circuit in the previous problem, calculate the amount of energy that the circuit
element absorbs between t = 0 and t = 1 .


I don't get the b0 part. The solution for the first part is 50 sin(t) cos(t) [W]. How do I get the amount of energy for that time frame?
 
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XodoX said:
1. A circuit element is shown below, with the voltage v(t) and the current i(t) defined. The
voltage and current are given as
v (t ) = 5sin (t ) [V]
i (t ) = −10cos (t ) [A] .
Calculate the power that the element is delivering.

b) For the same circuit in the previous problem, calculate the amount of energy that the circuit
element absorbs between t = 0 and t = 1 .


I don't get the b0 part. The solution for the first part is 50 sin(t) cos(t) [W]. How do I get the amount of energy for that time frame?


What kind of a circuit element is it? Why are they asking about delivering power in one part, and absorbing power in the other part?

To get energy over a time period, you just integrate the power multiplied by dt over the time interval.
 


I forgot how to take the integral of cos/sin :confused:

u= sin(t) du=cos(t) dt

Maybe you can explain the next step to me:) I think that once I got the result of it I am done.
 


XodoX said:
I forgot how to take the integral of cos/sin :confused:

u= sin(t) du=cos(t) dt

Maybe you can explain the next step to me:) I think that once I got the result of it I am done.

The wikipedia.org article on integration by parts is pretty reasonable:

http://en.wikipedia.org/wiki/Integration_by_parts

.
 
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