All values are for 20C. See the insulation guide. Resistance Wire. Calculator tool. Properties of Major Alloys. MWS Fe Cu Resistance Alloy Data. Download Data Sheet. Resistivity of some common materials. Common Alloy Trade Names. Search Submit Clear. About Us. About MWS. Company Profile. Industries Served. Lab Services. MWS History. New Oxnard Location. Resource Center. The Elektrisola Group. It is good at trapping heat, so it can be used to shield electrical wires like the nichrome that will be used in the experiment.
This way, the temperature and conditions of the environment will have minimal effect on the measurements on temperature received by the thermocouple. The purpose of this investigation is to find the relationship, if any, between the temperature of a nichrome wire and that wire's measured resistance.
We believe that increasing the temperature of the nichrome wire will cause the measured resistance of the wire to also increase.
This is because nichrome is composed of metals, and the resistivity of metals generally increases with temperature Bortner. The resistivity is directly proportional to the resistance, so the resistance should increase with the resistivity. Temperature is defined as the degrees Celsius of the wire measured with a thermometer. Resistance of the wire is defined as the voltage divided by the current in the wire. The controlled variables include but are not limited to the length of the wire, material used to make the wire, cross-sectional area of the wire, the fiberglass used to insulate the wire, the thermometer used, and the room environment in which the experiment is conducted.
The experiment included a piece of nichrome wire of at least 4 inches in length, electrical wiring, a voltage converter, two multimeters, a thermocouple, fiberglass insulation, and a thin glass tube. To set up the experiment, we used a voltage converter as a power source for a circuit. Electrical wiring was used to connect the voltage converter to the multimeters, with one used as a voltmeter and one as an ammeter. The electrical wiring also connected the voltage converter to both ends of a nichrome wire, shown in red in the diagram.
The nichrome wire was embedded in fiberglass insulation, which was used to ensure that the outside temperature would have a more limited influence on the measurement gained from the thermocouple. The fiberglass surrounded a glass tube. One end of the thermocouple was put into the glass tube, and the other end was placed in a styrofoam cup filled with iced water in order to create a large temperature difference between the two different ends and provide a more accurate temperature measurement.
To collect data, the voltage converter was used to change the voltage of the circuit, which also caused the temperature change. As the temperature was increased, data from the ammeter and the voltmeter were collected at certain intervals, with the first measurement being taken at room temperature measured as 23 degrees Celsius , the second being taken at 50 degrees Celsius, and the rest at 50 degree intervals until the temperature of degrees was reached.
In order to calculate the resistance, we utilized the Ohm's Law formula, which is voltage divided by the current. The results of the data demonstrates that as the temperature increased, the voltage and current increased as well, but the trend broke when it was at and Celsius degrees, which was reflected in our results for resistance; at and degrees Celsius there was a sudden peak.
As the temperature was increased, the voltage and current increased as well, but at and degrees Celsius, this trend was broken. This was reflected in our results for resistance when there was a sudden peak at and degrees Celsius. Resistance, so called because a resistor resists the flow of current being forced through it, arises from the interaction of the conduction electrons in the resistive element, in this case a nichrome wire, with the atomic lattice that makes up the element.
See demonstration This is analogous to friction, and it causes energy to be dissipated in the resistor as heat.
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