Checking my answer.... finding the power of a current and a voltage source

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Discussion Overview

The discussion revolves around calculating the power supplied by a current source and a voltage source in a parallel circuit configuration. Participants explore the implications of current direction and voltage in determining power, with specific values provided for voltage and current.

Discussion Character

  • Homework-related
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant calculates the power supplied by the current source using P=IV and arrives at 41.25W, expressing confidence in this result.
  • The same participant calculates the power for the voltage source using P=IV but questions the sign of the power due to the direction of current flow, arriving at the same value of 41.25W.
  • Another participant notes that if current exits the positive terminal of a voltage source, it indicates that the voltage source is supplying power.
  • A subsequent response reiterates the previous point about the current direction and power supply but also suggests that the voltage source could be absorbing energy, akin to charging a battery.
  • One participant suggests applying conservation of energy to the entire circuit as a method of verification.

Areas of Agreement / Disagreement

Participants express differing views on whether the voltage source is supplying or absorbing power based on the direction of current flow. The discussion remains unresolved regarding the interpretation of power in relation to the voltage source.

Contextual Notes

There is uncertainty regarding the visual representation of the circuit, which may affect the understanding of current direction and power calculations. Some participants cannot access the image, leading to potential misinterpretations.

EleventhFromHeaven

Homework Statement


The current source and voltage source in the circuit shown in the Figure below are connected in parallel so that they both have the same voltage, vs. The current source and voltage source are also connected in series so that they both have the same current, is. Suppose that vs = 15 V and is = 2.75 A. Calculate the power supplied (a) by the current source and (b) by the voltage source.
EAT_1186723673470_0_0154651397014097250.gif


Homework Equations


P=IV
(possibly) V=IR

The Attempt at a Solution


This seems pretty simple but I'm not very confident in my skills (first time doing a circuits class) I did P=IV for the current source and got 41.25W (which is correct). But for the voltage source, I got 41.25W. I want some clarification on this. I used P=IV but since the current exits the negative terminal, it's supplying power so it's positive.
 
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I cannot see a picture, but if current is exiting the positive terminal of a voltage source (entering negative term) then the voltage source is supplying power.
 
scottdave said:
It looks that site requires a login. Try screenshot or rightclick and download the picture, then upload here. Perhaps you are able to see it, because you are already logged into WileyPlus?
I cut this out of the screenshot, hopefully you can see it:
upload_2017-10-15_12-29-26.png
 
So it is as I had guessed. Current going into the positive of the voltage source means the voltage source is absorbing energy (or power), like when you charge up a Battery
 
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As a check.. apply conservation of energy to the whole circuit.
 
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