Solving an Electrical Circuit: Find Vo and Vb

[hani114]

Homework Statement

everything is attached in the image below

Homework Equations

Ip=In=0 Vp=Vn

The Attempt at a Solution

i used the two rules that vp=vn & ip=in=0

so i tink no current flows in Vc & Vd and the 60kohm resistor.. as for Va & Vb we apply kcl on the input voltage node and solve for Vo

current in Va is Ia and so forth.. and current in 375kohm(Re) resistor is Ie

so Ia + Ib + Ie = 0
Va/Ra + Vb/Rb + Vo/Re = 0
so we calculate Vo from that

for the second part we need to calculate the range for Vb so that -20<Vo<20
so i think we have to put Vo in terms of Vb and replace that in the range so that we get Vb

can anyone help me with this? it's late now and that's the best i can do..

 

[Redbelly98]

so i tink no current flows in Vc & Vd and the 60kohm resistor.. as for Va & Vb we apply kcl on the input voltage node and solve for Vo

Since the 60k is connected to ground, current can flow in from the Vc and Vd sources without going through the + pin on the op-amp.

 

[Mene]

I appreciate your effort in attempting to solve this electrical circuit problem. It seems like you have a good understanding of the basic principles and equations involved. However, I would suggest double-checking your calculations and making sure you have accounted for all of the components and their values correctly.

In order to solve for Vo and Vb, you can use Kirchhoff's laws and Ohm's law to set up a system of equations and solve for the unknown variables. It may also be helpful to redraw the circuit and label all of the components and their values for a clearer understanding.

As for the second part of the problem, you are on the right track by trying to express Vo in terms of Vb. This will allow you to determine the range of values for Vb that will result in a Vo within the given range. Keep in mind that you may need to use algebraic manipulations to rearrange the equations and isolate Vb.

Overall, my advice would be to carefully review your calculations and equations and seek assistance from a classmate or instructor if needed. Electrical circuit problems can be tricky, but with practice and attention to detail, you can successfully solve them.