Impermeable Brain

Rough draft for my physics write-up. I need to make one of these every week. They take hours to write. This is probably 2-3 hours worth of work and it's not finished!

THEORY
Capacitors store electrical energy. When a voltage is applied to a capacitor, it begins to charge (store) electrical energy. The maximum energy that the capacitor will store is equal to the maximum voltage applied to it. Upon removal of voltage, the capacitor discharges (releases) electrical energy. If left alone, a capacitor will release all of its energy. A capacitor will never fully charge, but in order to get as close as possible, a certain amount of time is necessary. The amount of time it takes for the capacitor to charge or discharge fully can be expressed as the RC time constant.
Two equations can be used in relation to the RC time constant; T = RC (T = time, R = resistance, C = capacitance) can be used with data collected from charging a capacitor, and ln(Vc/Vm) = [-1 / (RC)] * t (Vc = voltage of the capacitor at any given time, Vm = voltage of C at time t = 0, R = resistance, C = capacitance, t = time) can be used with data collected from discharging a capacitor.

EXPERIMENTAL PROCEDURE
The circuit was set up as follows:

The capacitor was charged over a period of 300 seconds, and the voltage on the capacitor was monitored and recorded using Data Studio. The capacitor was subsequently discharged, and the voltage was again monitored and recorded using Data Studio. Resistance and capacitance were found using experimental data acquired from charging and discharging the capacitor.

CALCULATIONS
Charging the capacitor
Calculation of resistance:
T = RC
44 s = R * 1 F
R = 44 ohms

Calculation of percent error:
Accepted value: 82 ohms
Experimental value: 44 ohms
(44 ohms – 82 ohms) / 82 ohms * 100% = -46.34%

Calculation of capacitance:
T = RC
44 s = 82 ohms * C
C = 0.54 F

Calculation of percent error:
Accepted value: 1 F
Experimental value: 0.54 F
(0.54 F – 1 F) / 1 F * 100% = -46%

Discharging the capacitor
Calculation of resistance:
Slope of the graph = (-1/RC)
-0.01078 = (-1/R*1 F)
R = 92.76 ohms

Calculation of percent error:
Accepted value: 82 ohms
Experimental value: 92.76 ohms
(92.76 ohms – 82 ohms) / 82 ohms x 100% = 13.12%

Calculation of capacitance:
Slope of the graph = (-1/RC)
-0.01078 = (-1 / 82 ohms * C)
C = 1.13 F

Calculation of percent error:
Accepted value: 1 F
Experimental value: 1.13 F
(1.13 F – 1 F) / 1 F x 100% = 13%

Percent difference between calculated capacitance:
Charging capacitance: 0.54 F
Discharging capacitance: 1.13 F
(1.13 – 0.54) / ((1.13 + 0.54) / 2) * 100% = 73%

Percent difference between calculated resistance:
Charging resistance: 44 ohms
Discharging resistance: 92.76 ohms
(92.76 – 44) / ((92.76 + 44)/2) * 100% = 71.31%

Messin' with the Grade Curve

I got a 102/100 on the bone test in A&P lab! I was so proud of myself. Now I just need to keep that up and maybe I'll get that A at the end of the semester...

Stinky Phallus

People Think I'm Awesome

Yesterday one of my fellow classmates asked me if I could tutor him for organic chem. I had to turn him down because I don't think I have enough time to fit it in my schedule.

My lab partner kept saying I was the best lab partner he had ever had - partially because I knew about 4chan and partially because I got a 100 on my org chem test and I was kicking ass on the lab questions.