Hello,
I am having trouble understanding how the power is analyzed for the current source in the attached circuit.
I have solved the circuit using the node voltage method and determined v0 to be +4 V with the polarities like this:
.
I then calculated the power dissipated by the resistors as follows:
R20 = (.2A)²(20Ω) = +.8 W,
R80 = (.2A)²(80Ω) = +3.2 W,
R25 = (4V)²/(25Ω) = +.64 W,
with the total power dissipated by the resistors as +4.64 W.
Then for analyzing the power for the sources, I have as follows:
VS = (24V)(.2A) = 4.8 W,
IS = (4V)(.04A) = +.16 W.
Adding all of these up I end up with total power dissipated at +4.8 W and total power produced at 4.8 W, which is great. The problem I am having is I know the current source is absorbing power but I do not know if I am calculating it correctly. I am assuming the voltage would be negative for the current source because the voltage is reversed from the voltage of the rest of the circuit. Is the way I did it above correct or would it be calculated with one of these options:
IS = (4V)(.04) = +.16 W or,
IS = (4V)(.04) = +.16 W?
Thanks in advance for any help, it is greatly appreciated.
I am having trouble understanding how the power is analyzed for the current source in the attached circuit.
I have solved the circuit using the node voltage method and determined v0 to be +4 V with the polarities like this:
.
I then calculated the power dissipated by the resistors as follows:
R20 = (.2A)²(20Ω) = +.8 W,
R80 = (.2A)²(80Ω) = +3.2 W,
R25 = (4V)²/(25Ω) = +.64 W,
with the total power dissipated by the resistors as +4.64 W.
Then for analyzing the power for the sources, I have as follows:
VS = (24V)(.2A) = 4.8 W,
IS = (4V)(.04A) = +.16 W.
Adding all of these up I end up with total power dissipated at +4.8 W and total power produced at 4.8 W, which is great. The problem I am having is I know the current source is absorbing power but I do not know if I am calculating it correctly. I am assuming the voltage would be negative for the current source because the voltage is reversed from the voltage of the rest of the circuit. Is the way I did it above correct or would it be calculated with one of these options:
IS = (4V)(.04) = +.16 W or,
IS = (4V)(.04) = +.16 W?
Thanks in advance for any help, it is greatly appreciated.
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