Understanding Power Equations: How Do You Solve for V2 and R in Ohm's Law?

AI Thread Summary
The discussion centers on a newcomer to a computer technician course struggling with basic electrical concepts, particularly Ohm's Law and power equations. The participant understands the fundamental equations (V=IR, R=V/I, I=V/R) but is confused by the introduction of V squared in power equations. It is clarified that power (P) is calculated as voltage (V) multiplied by current (I), and variations of this formula can be derived. The importance of grasping the physical meanings of voltage, current, resistance, and power is emphasized for better comprehension and job competitiveness. Further study and resources are encouraged to solidify understanding of these concepts.
ry12
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Hello everyone new here :)
I've recently enrolled myself in a computer technician course and I've encountered a few (basic) electrical sums.
I have absolutely no electrical background, and the course mentioned no requirement of such, but I'm already being presented with work I have no idea of. These past few days I studied electricity basics but I'm still struggling a bit.

I understood the concept of Ohm's Law, I think...
V=IR or R=V/I or I=V/R are the equations.

However I'm now being presented with V2 (squared) and I have absolutely no idea what to think, I'm mentally challenged. Any place I can look more into these?

The question I'm facing is: Power is equal to voltage multiplied by current. Add the missing information in each of the following power equations.
And the equations are: P=V_____, P=R_____, P=V2______.

[Moderator's note: Moved from a technical forum and thus no template.]
 

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ry12 said:
I understood the concept of Ohm's Law, I think...
V=IR or R=V/I or I=V/R are the equations.
Yes, those are right. Basically, they are looking to test your ability to manipulate those variations with another formula: P = V I.

For example you can combine P = V I with V = I R to get P = (I R) I, or P = I2 R

There are some helpful diagrams that go through all the combinations if you do an image search for Ohm's Law.
 
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ry12 said:
However I'm now being presented with V2 (squared) and I have absolutely no idea what to think, I'm mentally challenged. Any place I can look more into these?

The question I'm facing is: Power is equal to voltage multiplied by current. Add the missing information in each of the following power equations.
And the equations are: P=V_____, P=R_____, P=V2______.
lewando already answered your question.

If your computer technician course or program does not require, at the very minimum, basic algebra or introductory algebra, this would be surprising. Good basic arithmetic might be good but not enough.
 
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symbolipoint said:
Good basic arithmetic might be good but not enough.
Good point! I completely missed the opportunity to say that, while this may seem like a math exercise in manipulating symbols, you would be distinguished among your peers (of job candidates) if you could develop (and demonstrate, if asked) a physical comprehension of the terms: voltage, current, resistance, power and, of course, energy.
 
I'm familiar and studied algebra in the past, I'm just a bit mentally challenged about the squared and the question I'm being asked but I'll do more further studies and research. Thank you for your time!
 
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