Transfer function for RC and RL circuits

[evol_w10lv]

Homework Statement

I just want to understand, how to calculate transfer function.
Here is simple example:

Homework Equations

The Attempt at a Solution

But in this circuit I don't understand how to do it.

I have to find T and k as it is in preview. Which is the element for Vout in this circuit? Or what I shoud find first?

 

[NascentOxygen]

Start with what you want to find, then work backwards.

vout = (1/C).∫ i₂.dt

→ vout(s) = 1/(sC).i₂(s)

where i₂ is the current into the output capacitor, C2.

Now, find equations that allow you to substitute something for i₂. Keep going, applying Kirchoff's Laws as you work towards the left until you have vout in terms of vin but no other unknowns.

 

[rude man]

The impedance of a capacitor is 1/sC. So treat this network as impedances just as though the capacitors were resistors.

(This is per the fact that for a capacitor, i = C dv/dt or I = sCV so Z = V/I = 1/sC.)