Unknown Capacitance in AC circuit

Freq / V

  We assume that the circuit acts like a DC source at 30 Hz

Our calculations found that the capacitor was about 3.9 micro Farads 

DC Charge and Discharge of a Capacitor

Goal: Calculate the charge and discharge times for a capacitor circuit. Then conduct an experiment that shows agreement between theory and practice.

Task 1

Rth = (Rc)(Rl)/(Rl+Rc)

Vth = Vs/(Rc/Rl+1)

Step 1

 Step 2A

We found the Value for the Capacitor to be 525 micro Farads

 Step 2B

The resistor will be able to handle this max power because it is rated for 1 W and the max power is only 19 mW

Conducting the experiment

Blurry Picture of Set up

Time to charge

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It took approximately 20 secs for the capacitor to charge to 11 volts and 2 seconds to discharge which we calculated.

Leakage Resistance

Graph of Charge/Discharge

Conclusion:

The experiment was successful. Our calculations showed to be consistent with the experimental findings of charging and discharging the capacitor

Practical Signal Conditioning

Goal:
We were given a circuit component LM35 that delivered a voltage equal to that of the temperature in Celsius. However we are American we like to do things differently so we must change the temperature reading from the Celsius scale to Fahrenheit. We want to use and op amp to perform the operation converting Celsius to Fahrenheit. F = 1.8C + 32

LM 35 

Circuit diagram

Here we calculate R1 and R2 

Complete circuit with a voltage that is .782 Volts which is roughly what we were expecting

Since the resistors we used did not have the same exact values that we found we needed in our calculations our conversion was slightly off. 

Imaginary Number Computer Calculations

Computing imaginary numbers by hand can be tedious, so we like to use tools to make life more enjoyable.

Happy days, no need to rip hair out. Here is a sample calculation done on a calculator.