Michael+Circut+Lab

=Michael Circuit Lab= 2/3/10


 * Participants**: Michael Bateman.
 * Purpose**: The purpose of this lab is to understand how the current and voltage relate to eachother in three different kinds of circuts: Single-Resistor, Parallel, and Series. We also looked at how the current and voltage were related in Ohmic and non-Ohmic resistors.
 * Lab Documents**:


 * Brief Description of Experiment**: The purpose of this lab is to observe the relationship between current and voltage in a circut. For this lab I used the Phet.Colorado.Edu Circut Construction Kit (DC Only) simulation and I also made some real life circuits. In every circuit I made, I recorded the voltage at the battery, and the voltage across any/all of the resistors in the circut. I also used an ammeter to check the current in the circut. First I constructed a simple single-resistor circut with the Phet simulation, after I was confident with that circut i went on to build some more complicated circuts with the simulation, such as a series and a parallel circut. I looked for patterns in the voltage and current. After I did this on the simulation I then began to create some simple circuts with real wires, power supply, and resistors. For every different circut the lab told me to build (single-resistor, parallel, and series) I made sure i collected data for the battery voltage, resistor voltages, and the current through each resistor.


 * Data**:
 * __Table 1__**: Ohmic Resistor

__**Table 2:**__ Non-Ohmic Device (light bulb)

Parallel Circut
 * Circut Models:**
 * [[image:parallel.JPG]]

Series Circut with 3 resistors: **

Resistance = Volts / Amps || you will have I=Y V=X and since when there are no volts there is no current you can get rid of b. (1/R) is the only thing left to fill in the place of M. Slope = (1/R) || I also learned that some resistors have a constant resistance, and some do not. For example, a light bulb is an example of a resistor that does not have the same resistance, also known as non-ohmic. describe the major result of the experiment and how you arrived at thie result typically this will refer back to the purpose. For example, if the purpose was to find the coefficient of friction, you would write: The coefficient of static friction was determined to be 0.45. This was calculated from a measured angle using Newton's first law as desribed in the calculations.
 * Sample Calculations:** The only real formula that was needed to complete this lab is the Ohm's Law formula.
 * //Resistance calculation// || The resistance in Ohms was calculated by taking the measured voltage (V) and dividing by the current (A).
 * //Slope// || The slope of the line is equal to 1/(resistance) because: I=(1/R)V and the graph is a straight line (y=mx+b)
 * Results**: I learned from this lab that in a resistive circuit, when the resistors are in a series that the amps flowing through each resistor add up to equal the voltage from the battery. For example, if you have a 9V battery and 1 resistor the current will be .9 Amps, but if you have 2 resistors, the current through them will be .45 amps because .45 + .45 = .9. I also noticed that in a parallel circuit the current through each resistor is the same as the battery's voltage (9V battery = .9Amp current). In the parallel circuit the current going through the resistors adds up, and the sum of those currents is the same amount as the current going through the battery. If the current through your resistors is .9 amps, .3 amps, and 1 amp, the current going through your battery will be 2.2 amps, because 1+.9+.3 = 2.2.
 * Lab Questions**: Write out and answer any questions that are included as a part of the lab.
 * Conclusion**:This experiment did produce very correct, and reproducible results. Circuits are nice to do experiments like this on, because every time you test it, for the most part will stay the same. You can take the circuits apart, and put them back together without having to worry about it being messed up. The results always stayed the same, or very close to the same, because electrical circuits are mostly all controlled by equations, and if you put the right numbers into the right variables you will get the same numbers. The only part of this lab that was slightly confusing for me, may have been the power supplys, and multimeters because there were alot of knobs and it was easy to forget what settings you were on.

//Don't forget to link to your lab report from the lab reports page and to include a link to your lab report in your reflection.//