Capacitors Continued

So turns out that capacitors are really just like resistors that depend on the frequency of the signal fed to them.  A circuit with a resistor then capacitor will act like a voltage divider, so the "integrator" that I build last time will function if 1/wC << R, or when frequency >> 1/RC.
If we switch the Resistor and the Capacitor.... We get a "differentiator"! Math with circuits! who knew?
The "integrator" has another function, it can be used as a low pass filter ['low' frequencies are allowed to 'pass' through], since Vout = Vin *( 1/wc) / (R + 1/wc).  Consequently, the differentiator can also be used as a filter, but a high pass one. 


Questions for "Tuesday Feb 12th"

Lab 2‐2 in the Student Manual (An RC differentiator, experimentally)
   R = 1/wC = 1/(100kHz)(100pF)  = 100k
   Impedance at f = 0? R = infinity.  Impedance at f= infinity?  R = 0
Lab 2-4  Lowpass Filters
   f3dB Experimental = 1.2kHz; f3db Theoretical = 1.06kHz.  
   Phase shift at f3dB = -45degrees;  f << f3db = 0 degrees; f  >> f3db = -90 degrees
   Attenuation: 2f3db = 0.45; 4f3db = 0.25; 10f3db = 0.1.

Lab for "Friday Feb 15th"
Lab 2-5 Highpass Filters
    f3db = 1.2kHz again.
    Phase shift at f3dB = +45degrees;  f << f3db = +90 degrees; f  >> f3db = 0 degrees