Question

Electric current.
Problem: https://dl.dropbox.com/u/63664351/Current%20in%20Resistor.PNG

Answer 1

What is the magnitude of the current in the 40Ω resistor?

Answer 2

apply V=IR => I=V/R
so at 40ohm current must have been passed through 20ohm now you can find I=V/R

Answer 3

Are you saying at 40Ω resistor the current is I=13/60=0.22 A?
Enlighten me.

Answer 4

well current passed through 20ohm is V/R=13/20=0.65
and from other side you have a potential of 20V
that will be added too
so look it like this 13/(R1+R2) + 20/R2
got that???

Answer 5

Isn't that nodal analysis?

Answer 6

nodal???
whats that??

Answer 7

In your explanation, what is R1 and R2?
Can you please give detailed explanation?

Answer 8

R1=20 and R2=40

Answer 9

Are you saying that the magnitude of the current in the 40Ω resistor is
\[I_{40\Omega}=\frac{13}{60}+\frac{20}{40}=0.72?\]

Answer 10

according to me it is. . .

Answer 11

I believe you are wrong. There is no such answer on the multiple-choice.

Answer 12

then i must have done something slightly wrong let others see what's wrong. . .

Answer 13

Would you be particularly opposed to making a couple of Kirchoff loops and solving that way?

Answer 14

current should be added right???

Answer 15

The correct answer to the question is 0.33 A, solution forthcoming...

Answer 16

Here you go

Answer 17

1. Please explain in good details why \( I_{1} = I_2 + I_3 \) Is it because they are parallel?
2. You lost me on "which yield" line. How do you derive from the matrix form to next?

Answer 18

kirchoffs law of current current towards same point is added . . .

Answer 19

@theyatin Can you please explain it clearly? I hate pompous fools. Honest fools, like myself, are fine - I'd really glad if someone listen to my problems and try to help me. But guys who are fools and covering it all over and impressing people as to how wonderful they are with all this hocus pocus (with partial and ambiguous explanations) – THAT, I CANNOT STAND! An ordinary fool isn’t a faker; an honest fool is alright. But a dishonest fool is terrible!

@Jemurray3 Hey pardon me. It was a mistake of me on derivation of the matrix. I did solve it. However I still need explanation on why \( I_{1} = I_2 + I_3 \).

Answer 20

why current is added?
Ans: http://en.wikipedia.org/wiki/Kirchhoff%27s_circuit_laws#Kirchhoff.27s_current_law_.28KCL.29

Answer 21

is the answer 0.1 A ?

Answer 22

you have to use mesh analysis, here's da solution

Answer 23

if you dont know how to use mesh, den let me know

Answer 24

Hi @Tushara! Here is the available options:
A) 0.41A
B) 0.33 A
C) 0.77 A
D) 1.30 A

@ujjwal Hi having read your source. "At any node (junction) in an electrical circuit, the sum of currents flowing into that node is equal to the sum of currents flowing out of that node, or: The algebraic sum of currents in a network of conductors meeting at a point is zero."
On this problem where is the node of reference?

Answer 25

m sure what i did is right, i solved many circuits of this type, nd much more complicated ones, da question cud be wrong.......... but gudluck, i cant help yu more dan dat :)