Question

Math in electrical circuits ,

PLease help me understand the logic behind this
https://www.dropbox.com/s/oc1syc8fo6tqonb/Screenshot%202013-11-05%2015.02.00.jpg

Answer 1

in superposition theorem, we consider one source at a time,
so we need to switch off all other sources
you know how do we switch off voltage source ?

Answer 2

open circuit or short circuit ?

Answer 3

short

Answer 4

we plug it off like

Answer 5

yes

Answer 6

so, lets first take V1 first and switch off V2
can you find voltage across R3 then ?

Answer 7

v1*R3/R1+R2+R3 ?

Answer 8

how?
when we short V2, the R2 and R3 come in parallel right ?

Answer 9

V1R1R2R3/R1+R2+R3 ?

Answer 10

when you say parallel, what does this mean like for me and my formula ?

Answer 11

parallel means resistors in parallel...

Answer 12

alright

Answer 13

>.> parallel means parallel :P @hartnn lol

Answer 14

ok, our aim is to find v3 so i guess we need not do R2||R3

Answer 15

our aim is to find the value of x1 ?

Answer 16

read the question again ?
"The voltage v3 ....."
v3 is Voltage when only V1 source is on, which we need to find

Answer 17

aah my bad

Answer 18

ok

Answer 19

you know about nodal analysis ?

Answer 20

nodal analysis will give you equation in v3 directly

Answer 21

I may need to use this although I am a bit unsure

Answer 22

what do you do first for nodal analysis ? I remember I was using something liker his to fine the volt in random places

Answer 23

in nodal analysis, we use the fact that total current entering(or leaving) a particular node = 0
so, i1=i2=i3
got this ?