This preview has intentionally blurred parts. Sign up to view the full document

View Full Document

Unformatted Document Excerpt

Hampton Partner: 1 William Travis Hampton Date: 9/3/10 Ohms Law IElementary DC Circuits with Light Bulbs The purpose of this experiment was to see the relationship between current, resistance, power, and electric potential. The other aim was to learn about the different properties and setups of DC circuits including series and parallel circuits. The main focus behind the laboratory experiment is Ohms Law. It is defined as the relationship between the current I as it flows through a resistance R and the potential drop across it V (Contemporary Introductory Physics Experiments). The formula is: I=V/R where I = current; R = resistance; and V = the potential difference. The formula for power is: P=V x I where P = power; I = current; and V = the potential difference. The entire variables can be rearranged as P=VI=I^2R=V^2/R. There were many different apparatuses used during this experiment. A circuit board connected to a power supply that varied from 0 to 18 volts was the main component. Connecting the circuit board to the power supply were double banana plugs with wires that were connected across the terminals. Lastly, different banana plugs with light bulbs on top were used so that you could observe the intensity and resistance of the different circuits. 2 For Part of 1 the experiment, only one light bulb was used so the power and resistance was felt only upon that single light bulb. The relationship of voltage to power was linear. At 1 V, power was 0.996; at 18 V, power was 322.92. For Part 2, two light bulbs were situated next to each other. The current was split almost evenly between the two bulbs and the light on the first bulb was half as intense when the second bulb was added. The current and the power was the same with two bulbs as it was with one bulb. However, each bulb consumes fairly half the total power used by the two together. In Part 3, the two light bulbs were situated in parallel so that each light bulb consumed exactly half the power as the other light bulb. This time, however, the intensity of the first bulb did not change as the second light bulb was added. The total power and resistance were about the same as they were in Parts 1 and 2. In Part 4, a third bulb was added that was in parallel with the preceding two light bulbs. The front bulb had much more current than the back two because the back two were in a parallel setup so they shared the current. A possible error could have occurred if we did not place the wires in the appropriate positions so that the entire electric potentials were not covered. ... View Full Document

End of Preview

Sign up now to access the rest of the document