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glover_m
Nov1-09, 05:57 PM
1. The problem statement, all variables and given/known data

http://i60.photobucket.com/albums/h14/tokesh/Problem-1.jpg

2. Relevant equations

What is the current entering the node.

3. The attempt at a solution

I=V/R
P=IV -> 510/.470=1085V
R(Inductor)=wL -> 2pi*60*1.25 = 471.24
R(Resistor)=V/I -> 1085/0.47 = 2308.74
R(Total)= sqrt(R(Resistor)^2+R(Inductor)^2) -> 2356.12
V=sqrt(2)*V(RMS) -> 1534.42
I=V/R -> 1534.42/2356.12 = 0.65A

glover_m
Nov1-09, 08:42 PM
bump

vk6kro
Nov1-09, 09:39 PM
I=V/R
P=IV -> 510/.470=1085V
R(Inductor)=wL -> 2pi*60*1.25 = 471.24 Reactance in OHMS
R(Resistor)=V/I -> 1085/0.47 = 2308.74 OHMS
R(Total)= sqrt(R(Resistor)^2+R(Inductor)^2) -> 2356.12
You can't do this for parallel circuits. You have to work out the currents and then put them in the right angled triangle.

Don't forget that reactance is the term for the impedance of inductors and capacitors, not resistance which is purely for resistors.