Voltage & current

[Strathead]

V = IR and P = VI; it's as simple as that.

What's not so simple is figuring out which variables are held constant and which are allowed to change. Depending on that, increasing the voltage can result in either more current or less.

I beat you to it.

 

[Carultch]

There are many ways to look at this. First off it is math. Two concepts that HAVE to be grasped to understand electrical theory are "inversely proportional" and "directly proportional". These terms are absolute. Inversely proportional means that as one goes up the other goes down an equal amount so if I have 4 of one item and 6 of another item and I only have room for 10, if I add two of the first item, I have to take away two of the second item to maintain balance. Directly proportional means that as one goes up or down the other goes up or down mathematically the same. so if the ratio is 4 to 1, then when the one goes up to 2, the 4 goes up to 8.

That's not what inversely proportional means.

 

[Strathead]

That's not what inversely proportional means.

That is what it means unless you are trying to be picky that it is actually an equal proportion, not necessarily an amount. Where in the example I gave the two are interchangeable.

definition

A relationship between two variables in which the product is a constant. When one variable increases the other decreases in proportion so that the product is unchanged. If b is inversely proportional to a, the equation is of the form b = k/a (where k is a constant). Equation: y = 60/x.

 

[Qojoe]

Thanks guys for the responses, it definitly makes a little more sense, now i need to hit the books and play around with some circuits at home

Sent from my SAMSUNG-SM-N920A using Tapatalk

 

[Carultch]

That is what it means unless you are trying to be picky that it is actually an equal proportion, not necessarily an amount. Where in the example I gave the two are interchangeable.

definition

A relationship between two variables in which the product is a constant. When one variable increases the other decreases in proportion so that the product is unchanged. If b is inversely proportional to a, the equation is of the form b = k/a (where k is a constant). Equation: y = 60/x.

My point is, if X+Y=10, then that doesn't mean that X and Y are inversely proportional. It is true that one decreases as the other increases, but that relationship has nothing to do with proportionality. I'd call it an additive complementary relationship.


Inversely proportional would be X*Y=10, as you have clarified.