Physics 2426 Date 9/19/2011 Experiment: Electrical Method Mechanical Equivalent of heat
Group No 2
Objectives
The objective of this experiment is to determine experimentally where the heat comes from and how is it created; also to understand what the relationship between mechanical energy, electrical power and joule heating coming from a resistor submerged in water. Furthermore comprehend how to use an electric circuit depending on the use of an ammeter or a voltmeter using a parallel and a series circuit respectively. By the termination of this experiment we will be comfortable working with basic circuits.
Concepts
Historically the mechanical conversion of heat has been a concept with a great importance in the …show more content…
And finally we get the mechanical equivalent of heat Kh which is 4.817 j/cal .
Error Analysis
After finding the mechanical equivalent of heat, we find that our answer was wrong by about 15%. A lot of different reasons could influence that result such as; the current and voltage slightly changed during the whole experiment (it was supposed to be the same during the whole experiment). We also found that the wires and the cup were old and over used. We didn’t knew exactly how to work the stirring stick, that could also be a possible factor that affected our results because the more you stir the more heat you add to the water but the stirring was not constant during the whole procedure.
Conclusion
In conclusion, after finishing the experiment, now we understand how an electrical circuit works using a voltmeter, ammeter and DC power supply, we can also understand the danger involved and the risks if the circuit is not properly assembled by using parallel or series circuit. We also learned how the heat is created with energy sent through the wires. Finally, we learned that by knowing the voltage of a device we can determine how much energy we are going to use and how much money we are looking to