NCEES Question #111

[clemente]

Any one know how to explain the solution a little better. The transfer function T(s)= Y(s)/X(s) Output/input. V(s)/I(s), But then what...

I'm not getting this one..

 

[Ilan]

To find transfer function in the circuit, convert the circuit elements into s-domain.

R - R

C - 1/Cs

L - Ls

Once converted into s-domain, you can treat them like resistances in DC circuits.

In this problem, the transfer function is the ratio of voltage across the inductor to the current through the inductor. After converting the circuit elements, apply current divider rule to get the transfer function.

Current throught the inductor = I2(s) ...(1)

Voltage acroos the inductor = V(s) = I2(s)*Ls ...(2)

I2(s) = I(s)*R/(R+R1+Ls+(1/Cs)) ...(3)

substitute (3) in (2) and simplify to get (D)..

Ilan.

 

[clemente]

thanks for your help now i see what i was doing wrong