Use superposition to find the voltage VAB?
Attempt:
Firstly I short circuited the voltage source and put an open circuit instead of the current source so there were two circuits to analyse. I thought the best way to do this would be to find the current in AB first in both circuits and then subtract one from the other to get the current. Then use Ohms law to get the voltage AB. I can't seem to get the correct answer.
For the circuit with just the voltage source it is just a straight forward series circuit so I=Vs/Z
I = 5 Angle 90/3 Angle 0 = 1.66 Angle 90 Amps.
Is this correct? Have I made any errors when converting to polar form.
For the circuit with just the current source I thought it would be best to use the current divider rule. I think this is where I'm going wrong.
I = Is(j4/(3+j4//j4))
Is this formula correct? If not could someone tell me correct way to do it. I only need help with the currents. Thanks.
Attempt:
Firstly I short circuited the voltage source and put an open circuit instead of the current source so there were two circuits to analyse. I thought the best way to do this would be to find the current in AB first in both circuits and then subtract one from the other to get the current. Then use Ohms law to get the voltage AB. I can't seem to get the correct answer.
For the circuit with just the voltage source it is just a straight forward series circuit so I=Vs/Z
I = 5 Angle 90/3 Angle 0 = 1.66 Angle 90 Amps.
Is this correct? Have I made any errors when converting to polar form.
For the circuit with just the current source I thought it would be best to use the current divider rule. I think this is where I'm going wrong.
I = Is(j4/(3+j4//j4))
Is this formula correct? If not could someone tell me correct way to do it. I only need help with the currents. Thanks.
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