- #1

- 63

- 1

## Homework Statement

In my Intro to EE class we have a homework assignment with the following problem:

I think I finished part a but want to make sure that I am doing the problem correctly before I move on to the next part.

- Engineering
- Thread starter hdp12
- Start date

- #1

- 63

- 1

In my Intro to EE class we have a homework assignment with the following problem:

I think I finished part a but want to make sure that I am doing the problem correctly before I move on to the next part.

- #2

gneill

Mentor

- 20,875

- 2,838

- #3

- 63

- 1

what do I do about that?

- #4

gneill

Mentor

- 20,875

- 2,838

The current is specified as a cosine function of time. It has a frequency, so there's your ω for determining impedances. Its phasor will be just the magnitude of the cosine function since there's no phase shift involved.

what do I do about that?

- #5

- 63

- 1

Yeah?

- #6

gneill

Mentor

- 20,875

- 2,838

o Start by determining the operating frequency of the circuit: pull ω out of the time domain definition of the source.

o Write the current as a phasor value: For a cosine it's just the magnitude, so it's really simple.

o Use the ω from above and determine the impedances of the reactive components (jω stuff). Write them onto the circuit diagram.

o Write the node equations (or whatever other method you choose to solve for the required values).

- #7

- 63

- 1

What do I do with that i(t)? I think I'm supposed to know based on the phasor but I'm unsure

- #8

gneill

Mentor

- 20,875

- 2,838

Calculate values for the impedances of L and C. You've got the frequency and the component values, so do the calculations. Write those values onto your diagram.

- #9

- 63

- 1

Now what?

- #10

gneill

Mentor

- 20,875

- 2,838

When you've sorted that, the value for V2 will be the complex form of the phasor voltage for V2. You can find its magnitude and phase from the complex value.

- #11

- 63

- 1

61.54j-61.54

does that look right?

- #12

gneill

Mentor

- 20,875

- 2,838

Yes, that looks much better!

61.54j-61.54

does that look right?

So now you have the phasor for V2 in complex form. You can convert it to polar form: magnitude and phase, then write the time domain version from that.

- Last Post

- Replies
- 8

- Views
- 4K

- Replies
- 2

- Views
- 776

- Replies
- 20

- Views
- 3K

- Replies
- 34

- Views
- 3K

- Replies
- 7

- Views
- 4K

- Replies
- 3

- Views
- 574

- Replies
- 2

- Views
- 1K

- Replies
- 5

- Views
- 2K

- Replies
- 5

- Views
- 727

- Last Post

- Replies
- 4

- Views
- 1K