Current vs. Voltage

Sounds a lot like homework.

See for yourself:A blank current-voltage graph

xform,

You can get fooled if you just plug in any formula without understanding. For a fixed resistor (like a heater)

V = IR

That is Ohm's Law.

The power "consumed" is P = I² R

But, that's not a separate formula. The definition of power is

P Ξ VI or V = P/I

So, V = IR and V = P/I

P/I = IR

P = I²R

See, it's just one formula and one definition (I'm being a little loose with my use of "definition", but I'm old and ugly - humor me).

Sorry, i jus entered the wrong one, ohms law is V=IR and nt V= I^2*r....A typing error....Extremely sorry

Ohm's law states that the current through a conductor between two points is directly proportional to the potential difference across the two points, and inverselyproportional to the resistance between them.

The mathematical equation that describes this relationship is;

Power equation is P = VI, If we increase the power and voltage both, then the total current will also increase. This satisfy the Ohm's law which states that current is directly proportional to Voltage.

Vinu_Answers Sure_Answers

If the power or load in a motor remains same,if you reduce the voltage the current will increase and vice versa as P=VI

Did you notice although I increases with V,pf decreases.P=VIcosa

There are two equations

V=IR

P=V.I

(Note the use of . in one and not using it in another)

In total there are 4 unknowns, V, I, R, P

How can one say which is directly and which is inversely proportion when each of these are interdependednt ?

Let us forget about the electrical and consider two complex mathematical formulae

f(c_n) = f(a_n) x f(b_n)

Y(d_n) = f (c_n) . f(a_n)

And added to that there are overlaps ie if one looks at the parameters of each functions, there are some common ones

ie a_n ∩ b_n ≠ Nul

b_n ∩ c_n ≠ Nul

etc for all combinations

can you now say which one is directly and which one is inversely proportional? You can not even say which one is independent till you bring down all formulae to common base parameters and then relate.