This quote supports my prediction because say the lamp was my piece of wire and for every time the temp of the lamp goes up so dose the resistance, so as the length increases so should the resistance of the wire
METHOD: For my course work I am going to measure the level of resistance passing through a piece of wire at different lengths below is a circuit diagram of my apparatus
8v
METHOD: what I will change each time is:
- The length of the wire every 10cm up to 90cm
FAIR TEST: to make sure that it is a fair test what I will keep the same is:
- The diameter of the wire
- The type of wire (nichrome)
- The bulb
- The ammeter and voltmeter
- The amount of current passing thought (8 volts)
I will keep theses the same because they all have different resistors which would affect the results
I WILL: calculate the resistance within the piece of wire at different lengths by dividing the voltage by the current
Potential difference (V)
Resistance (onus) =
` Current (amps A)
THIS IS WHAT I WILL DO: I will set up my apparatus remembering to place my voltmeter parallel to the ammeter, I will then place my clip form the ammeter on the wire 10cm apart along with the clips for the voltmeter inside next to the other clips from the (A)
I will the allow 8volts to pass thought the wire while I take my results from both the ammeter and the voltmeter and record them on a table.
After this I will change the length of the wire to 20cm apart, keeping my voltmeter clips inside next to those from the ammeter and take the results yet again.
I will do this up to 90cm again recording my results on a table. Concluding this redo the experiment and take a second set of result which with the first set I will place them up on a graph and then draw a line of best fit so that I can compare and comntrast my results to my prediction>
RESULTS: These are the measurements I made; I can also show these results on graph
SET OF RESULTS NO. 1
SET OF RESULTS NO.2
CONCLUSION: What my results tell me is as the wire increases in length the resistance increases to.
I THINK THIS HAPPENED BECAUSE: I know that current is a flow of electrons, and the piece of wire is a solid which is dense. In a short piece of wire there are not many atoms for the current to pass thought so the resistance is small. But as the piece of wire increases in length so dose the number of atoms within the wire, therefore the greater the resistance.
To back up my prediction I have found a quote from the new edition physics book page 98, it reads:
“The resistance of a resister stays the same providing the temperature
Dose not change, but in a lamp the filaments dose change so its resistance changes. Some resistors are made so that we can change them when ever we want”
This quote supports my prediction because say the lamp was my piece of wire and for every time the temp of the lamp goes up so dose the resistance, so as the length increases so should the resistance of the wire
EVALUATION
MY RESULTS: my results are good enough to answer the question I was investigating because, the results that were taken prove my theory true, which was as the length increased the higher increase of the resistance, this was proven because as i changed my length i.e. 10cm to 20cm etc he resistance became bigger.
MEASUREMANTS: My measurement are accurate because all of the measurements
(bar 1 ) fitted the line of best fit and it was proven that there was a strong correlations.
ODD RESULTS: The results that did not fir the pattern were in the second set of results at the length of 40cm, the resistance was 5.91Ω and this did not fit the line of best fit
I THINK THIS BECAUSE: Maybe the result was caused by an inaccurate reading from the ammeter or voltmeter.
MY PLAN/GOOD RESULTS: My plan gave me good results because I used a well designed voltmeter/ammeter.
My calculations were to 2 decimal places and I took two sets of result to compare them.
HOW I COULD MAKE IT BETTER: I could make my experiment better by using a real quality ammeter and voltmeter and maybe I could change the voltage passing thought the wire. Or even I could change they type of wire and compare the results with Nichrome
