Current across resistor and inductor

AI Thread Summary
In a series circuit with a resistor and an inductor, the current flowing through both components is the same. Ohm's Law can be applied to the inductor using its inductive reactance, represented as I = V_L / X_L, where V_L is the voltage across the inductor and X_L is the inductive reactance. It's important to note that inductive reactance depends on the frequency of the applied voltage. The total current in the circuit can also be calculated using I = V_S / (R + X_L), where V_S is the source voltage. Understanding these relationships is crucial for analyzing circuits involving resistors and inductors.
verbose

Homework Statement


I have a resistor and an inductor in series. The current across each is the same, correct? I want to know if I can use Ohm's Law to solve for current across the inductor if I know the Voltage and inductive reactance. Basically, does I = V/X_{L} ?


Homework Equations



V = IR
I = V/R

does I = V/ X_{L} ?

The Attempt at a Solution

 
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??What do you mean by X_{L}? I can guess that V is the voltage drop, I the current and R the resistance. Is X_{L} the inductance? If so then, no, the voltage drop over an inductance is NOT given by the same equation as for a resistance. Surely you have that formula in your text?
 
X_{l}

by this i mean inductive reactance...sorry, it's tex syntax for X with L as a subscript. i have the habit of writing all my mathy stuff in latex syntax
 
verbose said:
by this i mean inductive reactance...sorry, it's tex syntax for X with L as a subscript. i have the habit of writing all my mathy stuff in latex syntax
Yes, I = \frac{V_L}{X_L}
Notice that X_L is dependent of the frequency of V_L
 
verbose said:

Homework Statement


I have a resistor and an inductor in series. The current across each is the same, correct? I want to know if I can use Ohm's Law to solve for current across the inductor if I know the Voltage and inductive reactance. Basically, does I = V/X_{L} ?


Homework Equations



V = IR
I = V/R

does I = V/ X_{L} ?

The Attempt at a Solution


Forget the problem for a minute, first let's clear up that current isn't across anything. Current flows through and voltage is established across. Like fingers on a chalk board.:cry:
 
If those 2 elements are in series (the resistor and inductor) and connected to a voltage source, the current through all elements will be given by:

I = VS / (R + XL)


If the voltage you are talking about is the voltage across the inductor, then yes, the current through all elements will given by:

I = VL / XL
 

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