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.
Resistance is voltage current 2 Formula: Using the same piece of wire throughout the experiment meant its temperature rose slightly over time, which may have affected my results. See Answer A gauge wire is wider than gauge wire and thus has less resistance.
Selection of reels of Eureka wire also known as Constantan or Contra of different gauges, e.
Again, I will record the voltmeter and ammeter readings and turn off the power pack. It could overheat and thus lead to the risk of fire. This was because I could plot a graph and show the general trend. This discharges the cell rapidly and can make it explode. Measure it five times to obtain accurate readings.
To do this we use the circuit shown in the diagram. Battery eliminator 1 To replace batteries in all the - circuits and provide power. Compiling data of the average resistance of bot the wires. Investigating the changing resistance of a wire as it heats up.
As shown by the equation, knowing the length, cross-sectional area and the material that a wire is made of and thus, its resistivity allows one to determine the resistance of the wire. However, using new pieces of wire each time would have been too impractical and time-consuming in the context of this lesson.
Ohm's law shows that resistance is inversely proportional to the current through a wire and directly proportional to the electrical potential, or voltage, which is measured in volts Giancoli, I could also consider using different cross-sectional areas of wires or even change the temperature of the wires deliberately and see how manipulating these variables affect the resistance of the wire.
Students will find it easier to measure at a prescribed length if they tape the wire to a metre rule with insulating tape and make connections with flying leads rather than crocodile clips. While the circuit was complete and on, the wires and the instruments used got hot.
The points are set in a line that slightly changes its direction, but prominently shows a variation in the ending. It is the power or the push to the electrical current. An alternative would be to use the p. I will switch off the power pack, move the crocodile clip that was at 5cm up to 10cm, and switch on the power pack.
The third circuit would consist an ammeter, a rheostat, a battery eliminator and the factors wire of two different lengths to investigate. Check Your Understanding 1.
Conductors of different length I will perform the experiment with two wires with different length. While testing with a voltmeter, while testing with a rheostat and with an ammeter. The variable I choose which is dependent on the independent variable factor and the controlled variables.
The water should be kept very well stirred. However, I think that unless I had specialist equipment the results would be distorted because the wire would eventually get very hot.
There are no anomalous results that I would consider to be far away from the line of best fit. If a gauge wire was used on the same circuit, then the breaker would allow up to 20 Amps to flow through it. Apparatus Ensuring Accuracy To ensure accuracy I will record the voltage and the current three times every 5cm and take the average reading.
Top Materials 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.
The investigation has enhanced my knowledge about the workings of different circuits and the elements involved.Explain that the resistance of the wire is equal to p.d.
divided by current; i.e. it is the gradient of the line from the origin to the point on the graph. Place a ruler on the graph, through the origin, and passing through the highest point on the graph.
Like the resistance to water flow, the total amount of resistance to charge flow within a wire of an electric circuit is affected by some clearly identifiable variables.
First, the total length of the wires will affect the amount of resistance. Sep 29, · How to set up a circuit with an ammetre and voltmetre to measure the resistance of a wire.
Mentions different thicknesses. The Resistance R is the resistance wire (constantan nichrorome) that you will be trying to calculate. Set the power supply to 1V. This limits the current through the wire in order to reduce any heating effect which may change the resistivity. Class practical A simple investigation of the factors affecting the resistance of a wire.
This experiment can be used as a more open-ended investigation.
Students can select the variables, the ranges of results and the equipment used. Students will find it easier to measure at a prescribed length if they tape the wire to a metre rule.
In this experiment the resistance change in a wire will be cross-sectional diameter of the wire affects the resistance. Variables The input variable will be the thickness of the wire to the nearest - Resistance of Wire Investigation In this investigation we are going to test our theory in relation to resistance of the wire.