Hi everyone!
I am currently studying for my exam and thought this would be a nice place to ask about some stuff I wondered about.
The question is:
Find the power associated with each source in the circuit (Circuit 2 is attached as a picture) and state weather the source is delivering or absorbing power. I used the node-voltage method to find out what i(a) was. (i(a) = 2A). Than, to find the power associated with the 50 V source is (p = vi) 50 x 2 = 100 W. However, the book says that it is not supposed to be 100 W but -100 W. So, my sign is wrong.
I wonder, why is my sign wrong? Because I have attached a second picture (Circuit 3) which I believe models the situation in this case, and according to that model power should be positive.
Is the power perhaps negative because a voltage source always delivers power?
I am currently studying for my exam and thought this would be a nice place to ask about some stuff I wondered about.
The question is:
Find the power associated with each source in the circuit (Circuit 2 is attached as a picture) and state weather the source is delivering or absorbing power. I used the node-voltage method to find out what i(a) was. (i(a) = 2A). Than, to find the power associated with the 50 V source is (p = vi) 50 x 2 = 100 W. However, the book says that it is not supposed to be 100 W but -100 W. So, my sign is wrong.
I wonder, why is my sign wrong? Because I have attached a second picture (Circuit 3) which I believe models the situation in this case, and according to that model power should be positive.
Is the power perhaps negative because a voltage source always delivers power?
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