For the following circuit assume that vi 1V and find the fo

For the following circuit, assume that v_i = 1V and find the following. Express all your answers in engineering notation. Assume the op-amp is ideal. i_1 = i_2 = i_3 = v = v_o = What is the input resistance of the circuit as seen by the signal source? R_in =

Solution

1)where i1=V1/R1=1/20K=0.05mA

2)when the opapm is ideal V⁺=V^-,the node volatge at +ve terminal of opamp is Zeor,then negative terminal voltage V^-=0

then i₂=V^-/R₂=0/20k= 0

so  i₂=0;

(iii)where  i₃= i₁+ i₂ =0.05m +0=0.05mA

(iv)V_-=0V since V₊=V_{- and} V_{+ is grounded so} V₊₌₀

_V)V₀=-I₃R₃=-0.05m*100K=5V

The input resitance for this circuit we need to consider only R1, so the input resitance is 20Kohm