The problem is in the image attached. I tried doing nodal analysis at A and B, and then solving, getting
j*ω*C*Va - I1 + (Va-Vb)/(R+j*ω*L1) - I3 = 0
Vb/(j*ω*L2) + (Vb-Va)/(j*ω*L1+R) -I2 + I3 = 0
plugging in
(Va-Vb)/(.5+j*.5) + 2x*j = 2
Vb/j + (Vb-Va)/(.5j+.5) = 0
My answers:
0.20 cos(t-81.9)
0.40 cos(t-63.4)
, but the answer is only half correct (10/20 pts). I'm not sure if it's the amplitude or angle that's wrong.
I used this (x= Va, y= Vb, i = j) in the link below
http://www.wolframalpha.com/input/?i=(x-y)/(.5+i*.5)+++2x*i+=+2,+y/i+++(y-x)/(.5i+.5)+=+0
Then for the second part I tried ignored I1 and I2 and did the same thing with nodal analysis
x*(4j) + (Va-Vb)/(.5+j) = 1
(Vb-Va)/(.5+j) + y/(2j) = - 1
but I end up with an answer that's completely wrong.
(x= Va, y= Vb, i = j) in the link below
http://www.wolframalpha.com/input/?i=x*(4i)+++(x-y)/(.5+i)+=+1,+(y-x)/(.5+i)+++y/(2i)+=+-+1
j*ω*C*Va - I1 + (Va-Vb)/(R+j*ω*L1) - I3 = 0
Vb/(j*ω*L2) + (Vb-Va)/(j*ω*L1+R) -I2 + I3 = 0
plugging in
(Va-Vb)/(.5+j*.5) + 2x*j = 2
Vb/j + (Vb-Va)/(.5j+.5) = 0
My answers:
0.20 cos(t-81.9)
0.40 cos(t-63.4)
, but the answer is only half correct (10/20 pts). I'm not sure if it's the amplitude or angle that's wrong.
I used this (x= Va, y= Vb, i = j) in the link below
http://www.wolframalpha.com/input/?i=(x-y)/(.5+i*.5)+++2x*i+=+2,+y/i+++(y-x)/(.5i+.5)+=+0
Then for the second part I tried ignored I1 and I2 and did the same thing with nodal analysis
x*(4j) + (Va-Vb)/(.5+j) = 1
(Vb-Va)/(.5+j) + y/(2j) = - 1
but I end up with an answer that's completely wrong.
(x= Va, y= Vb, i = j) in the link below
http://www.wolframalpha.com/input/?i=x*(4i)+++(x-y)/(.5+i)+=+1,+(y-x)/(.5+i)+++y/(2i)+=+-+1
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