JS+SF

Problem: How do different voltages affect the speed of a dc motor?
 * Variation of voltage on dc motors**

Hypothesis: If a higher voltage is applied to a DC motor then it will turn faster.

__Procedure__ 1) Hook the motor up to battery or power supply with alligator clips 2) Use the tachometer to measure how fast the motor is turning 3) Insert speed of motor into the table below 4) Repeat above steps 7-10 times for each voltage

__Materials__ Basic DC motor, tachometer, wires with alligator clips, power supply or batteries of several voltages
 * = Trial ||= 5 volts ||= 10 volts ||= 15 volts ||= 20 volts ||
 * = 1 ||= 833.55 rpm ||= 985.95 rpm ||= 2042.8 rpm ||= 3966.2 rpm ||
 * = 2 ||= 834.28 rpm ||= 921.06 rpm ||= 1452.6 rpm ||= 3996.7 rpm ||
 * = 3 ||= 835.25 rpm ||= 930.40 rpm ||= 1649.0 rpm ||= 4034.3 rpm ||
 * = 4 ||= 838.71 rpm ||= 1041.2 rpm ||= 1814.2 rpm ||= 4050.6 rpm ||
 * = 5 ||= 839.42 rpm ||= 1003.9 rpm ||= 1912.3 rpm ||= 4079.7 rpm ||
 * = 6 ||= 833.61 rpm ||= 1074.7 rpm ||= 2091.2 rpm ||= 4091.5 rpm ||
 * = 7 ||= 842.50 rpm ||= 1074.3 rpm ||= 2355.8 rpm ||= 4123.0 rpm ||
 * = 8 ||= 840.14 rpm ||= 1052.1 rpm ||= 2591.9 rpm ||= 4133.9 rpm ||
 * = 9 ||= 834.88 rpm ||= 1032.8 rpm ||= 2835.0 rpm ||= 4149.1 rpm ||


 * = Trial ||= 5 volts ||= 10 volts ||= 15 volts ||= 20 volts ||
 * = Averages ||= 836.9 rpm ||= 1012.9 rpm ||= 2082.8 rpm ||= 4074.1 rpm ||


 * November 14, 2011 -** Started work in mph but switched to rpm because shaft speed is what's being measured.
 * November 15, 2011 -** All data is recorded, chart is done and pictures were taken. There weren't any things to change other than occasionally adjusting the motor to get a better contact with the tachometer**.**


 * Abstract:** This experiment was designed to test changes in a motor's rotational speed from a varyation of voltages. This was accomplished by attaching a dc motor to a power supply at different voltages. The motor was zip tied to a rig that held it firm and in place that the tachometer could be attached to for the most precise readings possible. Some of the results were suprising for the size of the motor such as at 20 volts it was turning at an average of 4074.1 rpm. That is an astounding number for that motor as it was designed to operate normally at less than half that voltage. As far as any applications there are tons of major corporations doing reasearch and working on making electric motors that are more efficient and faster. There was a good deal of research done and put into this experiment but there are several thousands of different types, styles, and makings of electric motors so choosing one to use is hard but considering the variables being voltage and rpm a smaller motor was necessary.


 * Experimentation:** This experiment was essentially to see if amping up the voltage could make a dc motor turn any faster, which was found to be highly possible. The problem was to see how different voltages change the performance of the motor while the hypothesis stated a higher voltage woud turn faster. This turned out to be true with suprisingly tight result groupings as there were minor fluctuations in power there are apparent fluctuations in the results recorded. The procedure was simple hook up power supply and motor and set the voltages accordingly. Then take a reading with the tachometer and


 * Discussion:** When the data is analyzed it seems to be good well set up data, this is because it is in very small groups varying only slighty answer by answer. The data is also extremely conclusive where the higher voltages do raise the speed substatially. As clear from the graph there is a tremendous step up from one voltage to the next leading to the conclusion that the hypothesis was correct. The experiment could have been better if a sturdier rigg was used as the motor slid some and needed reset several times. There was also the problem of having to check the voltage before every trial so a better power supply with less fluctuation and a more accurate voltmeter. The motor was blown out when a tenth trial was tried it satrted to turn over and then sparked which blew the insides all out of place which it then broke out of the zip-ties and shredded the mount so use of a higher rated motor is well advised. As far as any sources of error go the tachometer slipped several times from the motor wanting to slide back through the zip ties and it would move around slightly making the readings slightly off on occasion.


 * Conclusion:** The hypothesis of this project was correct and anwsered the problem. This was because when the higher voltages were applied the motor turned faster and vice versa. This all because of the strength of the charge determines the magnetism of the electro-magnet in the motor causing it to turn faster. When a lower voltage is applied then the brushes take longer to gain their charge causing the motor to turn over slower. At times if the voltage is low enough the motor can seem to be visibly and audibly jumpy.


 * Applications:** This experiment has a massive array of real-world applications. Things such as factories could use either a higher voltage or a more efficient motor to run mills and lathes so they operate smoother and more productively. This could also be used for someone who is in to remote controlled cars to upgrade their car while keeping in a set budget. The experiment could be expanded by use of several motors of varying size and shape, as well as a different broader range of voltages both higher and lower. Also a more precise way to set voltage as fluctuation was a problem.