Parallel voltage sources circuit


by Femme_physics
Tags: circuit, parallel, sources, voltage
Femme_physics
Femme_physics is offline
#37
Jul8-11, 10:22 AM
PF Gold
Femme_physics's Avatar
P: 2,551
I intended to ask for the power dissipation in the 4 ohm resistor that is between A and B.
Easy peasy!

P2 = 2 x 5.211^2 = 54.31 [W]

I give you the smurfs. All of them are yours, you *evil* you!
Muwahhaahahhah!!!!

Btw, the total power is the sum of the powers dissipated in each of the 3 resistors.
You mean
Pt = Power dissipated in resistor 1 +Power dissipated in resistor 2 + Power dissipated in resistor 3?

In which case, I was aware of that!

And I did get the correct result, yes?
I like Serena
I like Serena is offline
#38
Jul8-11, 10:36 AM
HW Helper
I like Serena's Avatar
P: 6,189
Quote Quote by Femme_physics View Post
Easy peasy!

P2 = 2 x 5.211^2 = 54.31 [W]



Muwahhaahahhah!!!!



You mean
Pt = Power dissipated in resistor 1 +Power dissipated in resistor 2 + Power dissipated in resistor 3?

In which case, I was aware of that!

And I did get the correct result, yes?
Let me see...

We got a total power of 258.65 W.
Subtract 199.46 W from your previous result.
Subtract another 54.31 W that you just got.

That leaves.... 4.88 W for the 4 ohm resistor between A and B.
Yes! That's it! You got it!
Femme_physics
Femme_physics is offline
#39
Jul8-11, 10:48 AM
PF Gold
Femme_physics's Avatar
P: 2,551
w00000000000000000t

You rock!


I'll probably do the other one tomorrow^^ You're incredible, ILS!!! This is pretty fun for me, I don't know about you You're a life saver. I'm pretty stressed about term B in electronics, it's my last chance at "redemption" for this course.
I like Serena
I like Serena is offline
#40
Jul8-11, 01:15 PM
HW Helper
I like Serena's Avatar
P: 6,189
Neh, this is no fun for me. ;)
Ouabache
Ouabache is offline
#41
Jul8-11, 03:44 PM
Sci Advisor
HW Helper
P: 1,327
You did a nice job !! (!עבודה טובה)
There are typically several approaches to the same question.
Some take fewer steps than others.

Here is the method I was suggesting you try.
(It may help save you some time on an exam)

You found currents for the initial question to be I1=1.105, I2=5.211A and I3= I0 = 6.316A

Next was find VAB and PAB (with respect to R1).

V= IR ; VAB = I1R1 = (1.105)(4) = 4.42V
P = IV; PAB = I1VAB = (1.105)(4.42) = 4.88W
Femme_physics
Femme_physics is offline
#42
Jul8-11, 08:27 PM
PF Gold
Femme_physics's Avatar
P: 2,551
Duly noted Quabache

Next time I will certainly be wiser

I will try me hands on another exercise this morning (it's 4:30 AM here. I'm an early riser!)
Femme_physics
Femme_physics is offline
#43
Jul9-11, 12:52 AM
PF Gold
Femme_physics's Avatar
P: 2,551
Quote Quote by I like Serena View Post
And here's a second one.
Perhaps you can start a separate thread for this problem?


For the circuit shown below, determine the voltage for each of the
resistors and label the values on the diagram.
That was pretty easy. I didn't find P for each just for lack of patience. I know I know it!

I like Serena
I like Serena is offline
#44
Jul9-11, 01:17 AM
HW Helper
I like Serena's Avatar
P: 6,189
Hmm, it seems you've been progressing.....

But wait! You did not get all the smurfs!
Which smurf did you miss?
Femme_physics
Femme_physics is offline
#45
Jul9-11, 01:19 AM
PF Gold
Femme_physics's Avatar
P: 2,551
Yea I know finding the P in each of them...but com'on you just apply a formula it's soooooooooooooo easy! Lemme skip that pretty please?
Femme_physics
Femme_physics is offline
#46
Jul9-11, 01:22 AM
PF Gold
Femme_physics's Avatar
P: 2,551
Quote Quote by I like Serena View Post
How about this one?

First question--

How come they get to pick for me the direction of I? Shouldn't I be the one determining it?
I like Serena
I like Serena is offline
#47
Jul9-11, 01:24 AM
HW Helper
I like Serena's Avatar
P: 6,189
Not that. You made a mistake.
Perhaps I should have said that you dropped a smurf?
I like Serena
I like Serena is offline
#48
Jul9-11, 01:28 AM
HW Helper
I like Serena's Avatar
P: 6,189
Quote Quote by Femme_physics View Post
First question--

How come they get to pick for me the direction of I? Shouldn't I be the one determining it?
Well....

Look at the drawing in your first post in this thread.
You did not mark the directions of the currents (and as a consequence you made a mistake with it).
So I thought I'd better mark them for you!

(Just kidding, I just picked the first exercise that fitted your description. )

The real reason would be that the people who made the exercise would want the same answer from all students, so it's easier for them to check the answers. This means naming the currents and preselecting the directions.
Femme_physics
Femme_physics is offline
#49
Jul9-11, 01:52 AM
PF Gold
Femme_physics's Avatar
P: 2,551
Quote Quote by I like Serena View Post
Not that. You made a mistake.
Perhaps I should have said that you dropped a smurf?
More like a typo! I've accidentally linked the wrong file

Femme_physics
Femme_physics is offline
#50
Jul9-11, 01:55 AM
PF Gold
Femme_physics's Avatar
P: 2,551
Quote Quote by I like Serena View Post
Well....

Look at the drawing in your first post in this thread.
You did not mark the directions of the currents (and as a consequence you made a mistake with it).
So I thought I'd better mark them for you!

(Just kidding, I just picked the first exercise that fitted your description. )

The real reason would be that the people who made the exercise would want the same answer from all students, so it's easier for them to check the answers. This means naming the currents and preselecting the directions.
Interesting. So you get different answers if you pick different direction for I? I didn't know that!
I like Serena
I like Serena is offline
#51
Jul9-11, 02:03 AM
HW Helper
I like Serena's Avatar
P: 6,189
Quote Quote by Femme_physics View Post
More like a typo! I've accidentally linked the wrong file
Yep! You found the smurf! :)

Quote Quote by Femme_physics View Post
Interesting. So you get different answers if you pick different direction for I? I didn't know that!
If you pick the direction of a force in mechanics in the other direction, don't you get a different answer too?
Femme_physics
Femme_physics is offline
#52
Jul9-11, 02:15 AM
PF Gold
Femme_physics's Avatar
P: 2,551
Yep! You found the smurf! :)
No, no! I already had the smurf, I just mispointed on him! Like, it's totally not fair that you think I had to correct myself I already fixed that typo!!! grrr!!! I wrote the answer at the second line instead of doing the equal sign and stuff.....ah nevermind you wouldn't ever believe me anyway!! *storms off*

*comes back*

Oh right there's an exercise to solve. But if I didn't have....if I didn't....I'd so storm off right now!


As if!

If you pick the direction of a force in mechanics in the other direction, don't you get a different answer too?
You get the same value, just with a minus or plus
Femme_physics
Femme_physics is offline
#53
Jul9-11, 02:18 AM
PF Gold
Femme_physics's Avatar
P: 2,551
Hmm.... would it be reasonable to ask an easier parallel voltage sources problem before I try this one? I really want more practice on basic circuits with parallel voltages first...unless you think it would be redundant to me now? Whatever you tell me
Femme_physics
Femme_physics is offline
#54
Jul9-11, 02:28 AM
PF Gold
Femme_physics's Avatar
P: 2,551
I've really decided it's too complex since we're not gonna have something THAT difficult on the test!


Register to reply

Related Discussions
Electronic parallel voltage sources exercises? Engineering, Comp Sci, & Technology Homework 48
Two Parallel Voltage sources and KVL Electrical Engineering 2
Nodal analysis algorithm applied to a circuit without voltage sources Engineering, Comp Sci, & Technology Homework 3
Voltage and current sources; circuit Introductory Physics Homework 1
Finding current across a capacitor in a circuit with two AC voltage sources Introductory Physics Homework 13