In all power supplies there is a potential difference between its two-opposite terminals. These terminals are usually denoted as positive and negative and if a wire with a resistor is hooked up to each end of the power supply charge can be moved through the wire. The movement of charge is called the current and it caused by electrons that move in a metal wire. If a power supply maintains a constant across a resistor we can calculate the value of this current by using Ohm’s law. Ohm’s law is I=V/R and this works if the resistance value is constant. This law cannot be applies everywhere however because not everything has a constant resistance. When the temperature of a metal increases there are more electron collisions, which will cause the current to decrease. In the zener diode there is not a constant resistance either, they operate on a reverse bias and can function at a very high resistance until the voltage is raised above a certain value.
This experiment was broken up into five different sections with the first section being the manual measurement of resistance. The purpose of this was to measure voltage versus current through a resistor to see that it follows a straight line with a slope equal to the resistance. The second part of the experiment was to use the computer sensors to measure the resistance of the same circuit. Then we hooked up the circuit to a resistor with a different value to see what effects it would have on the circuit. In part four Ohms law was violated to see what effect thermal properties had on the circuit. Finally in part five we used the zener diodes to see what their overall effect would be when placed into the circuit.
The experiment began by hooking up the ...
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... to level out and stops increasing all together.
`In conclusion this lab was done as instructed and all values with their uncertainty values were obtained. This lab provided a great demonstration of Ohm Law which is V=IR. Two different methods were used to find resistance values, first a manual method was used and the resistance was 60.59Ω and with a computer sensor and that value was 48.33Ω. The computer was more accurate mostly likely because it was able to get more accurate measurements than a human is able to get. Then Ohms law was violated with thermal effects and that generated two different resistances at different high and low currents. Finally zener diodes were used to violate ohms law to show how there is a voltage threshold, which causes resistance to eventually level out and become constant. This lab provided a great understanding of Ohms law.
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