What is the voltage across the resistor?

[JayLewis]

Homework Statement

The amplitude of the voltage across an entire series circuit is 17 V. The inductor alone has an amplitude of 30 V and across the capacitor it is 22 V. To the nearest tenth, what is the voltage across the resistor?

Homework Equations

The Attempt at a Solution

(17+8i)(17-8i)

289+64
square root of 353
18.8

 

[gneill]

Homework Statement

The amplitude of the voltage across an entire series circuit is 17 V. The inductor alone has an amplitude of 30 V and across the capacitor it is 22 V. To the nearest tenth, what is the voltage across the resistor?

Homework Equations

The Attempt at a Solution

(17+8i)(17-8i)

289+64
square root of 353
18.8

Hello JayLewis, Welcome to Physics Forums.

Can you explain the reasoning behind your attempt?

 

[JayLewis]

I was trying to follow steps from handout

I was trying to follow steps from handout..this is the first time we have worked onthis and I don't understand it.

 

[gneill]

Okay. I see that you're making use of complex numbers, so I assume that you're familiar with (or at least learning about) the concept of complex impedance and voltage and current. Is that right?

 

[JayLewis]

we are learning about it now

but the instructions aren't very clear

here is the rest of my work:

374-510i
_________
484+900

374-510i
_________
1384

.27-.37i
.07+.14
.21

 

[gneill]

but the instructions aren't very clear

here is the rest of my work:

374-510i
_________
484+900

374-510i
_________
1384

.27-.37i
.07+.14
.21

It's difficult to comment on your work since it's not annotated. What is it you're doing here?

If I may make a suggestion, suppose you consider the series RLC circuit being driven by a fixed AC current source. What would be the complex values of the potentials across the capacitor and inductor?