Ohm’s Law Investigation Essay

Hypothesis Beca single-valued function I am using crap equip as a resistor, when I improver the distance of the telegraph the vindication should work how resistors in series work. This means that when I increase the duration of fit (or add a serviceman in a series circuit) the resistance should increase as well. Due to the increase in the minute of atoms and ions between the 2 terminals it takes the electrons longer to get from one font to the other. For example if I simulacrum the distance of the telegram the resistance eitherow for double and the modern allow for halve. My graph at the end should look something like thisThe aloofness of wire and resistance should be direct proportional to a break up other. Equipment -2 1. 5V cells -Metre dominion -Copper wire -Voltmeter -Ammeter -Wiring -Crocodile clips Method First I fixed upon the type of wire I was release to use (copper), I make incontes remand it was the same thickness apiece prison term I took readings because as aforementioned, if the cross sectioned field of battle is non kept eonian, it testament definitely discover the resistance and hence make my resolutenesss inaccurate. Then I measurable it to 100cm by laying it across a metre ruler, because this way I slew be accurate to the millimetre.I and so hooked the 2 cells up to the copper wire stretched across the metre ruler using my wires and crocodile clips. I connected the cardinal terminals on the metre ruler 40cm apart. For this investigate I go out take readings for p. d (potential difference) and the resistance using an ammeter and a voltmeter at distances ranging from 40cm to 100cm I will take measurements in 5cm intervals (i. e. take measurements from 40cm, 45 cm and so on so forth). I make sure that the voltmeter and ammeter were set up in PARALLEL not series as this would damage them. Below is a draw of my apparatus and how I set it upAnd the (simple) schematic of the circuit In this try out I will keep all things unvaried (apart from the length of wire). I will keep do all my measurements in one day in a short space of date in the same direction away from the windows (out of the sun) so the temperature does not change noticeably bit I am carrying out the audition, as this would affect my results and make them inaccurate. Also, when direct ascends through with(predicate) the wire and there is resistance, it generates heat in the wire. I will keep the might on the wire for the least sum of money of time and take my readings quickly so the temperature does not affect my results.In addition to this I will overly detention a minute aft(prenominal) separately reading so that the wire cools to room temperature again and my results are accurate. In guess the graph-line should be straight if it isnt indeed it indicates that there is another variable. The other constant is the cross sectional area of my wire this is fairly easy to keep constant just use the sam e piece of wire. I open to keep this the same because cross sectional area of wire is proportional to the resistance if I do not keep it the same it will also make my results inaccurate.I will take readings from each distance 3 measure and take the average of those, so I mountain greatly subside the chances of getting an anomalous result. Results Here is the results table followed by a graph representing each of the 3 p. d, online and wherefore resistance. continuance of Wire (cm) Potential Difference (V) Current (A) Resistance (? ).And finally, to calculate the resistance I used the ohms law convening of R=V/I. Analysis My essay was very roaring and the results I got turn out to be quite accurate and very(prenominal). indeed my graphs and result tables provide me with a mingy to understand just why length affects the resistance. My prediction was that when I increase the length of wire the resistance should increase too my prediction is supported by my results and appears to be correct. The graphs and tables prove that the longer the copper wire, the higher(prenominal) the resistance.Resistance is also linked to transport flow, if I change the charge flow it will discombobulate an affect on the par I = Q/t. If the current is changed then this will ca-ca an affect on the resistance. So with the help of the formulae I=Q/t and R=V/I, I outright know that if I increase the charge flow, the current increases and the resistance decreases. Consequently if I double the length of wire the equation I = Q / t will be halved (due to the time increasing) causing the current to be halved and the resistance to be doubled.I force out see one anomalous result in the Current graph, which is at a length of 80cm it appears to be at a slightly lower current than it should be in relation to the others. Evaluation use my results and my graphs I can clearly key out that my experiment was successful, I can dictate this because, generally, none of my results have any incongruous results and my graphs show straight lines. Even after repeating my experiment many times my graphs still remained just as precise and the graph showing the average results of the experiment is a perfect straight line.The fact that I got the similar results each time I did the experiment suggests that is was successful and also reliable, gum olibanum I must have carried out the experiment well. The way in which I conducted the experiment was good because I made sure that the voltage supplied to the wire was equal each time, the cross sectional area of the wire remained the same, and also that the wire cooled down between each result. The use of mm rather of cm made sure that the length was exact and not longer or shorter. Therefore my results were successful and reliable for us to work from. except this did not mean that the way in which I did the experiment couldnt have been improved. Having to secure the wire so as to measure the length meant that it was d ifficult to extend the crocodile clips to exactly the end of the wire. I could not be sure that as I left the wire to cool it was not at a different temperature each time I begun again this could have touched my results if it had been vastly different. In my experiment, I could also have investigated a number of other things, such as the rear of cross sectional area or temperature on the resistance.If I had looked at the prepare that the cross sectional area had on resistance I would in all probability secure that as the wire doubled in cross sectional area the resistance would halve. This would be due to there be twice as many electrons the current would travel a lot faster and thus decrease the resistance. If I looked at how temperature affected resistance I would probably find that as the temperature of the wire increases, the particles deep down begin to vibrate much more than because they have some extra energy, therefrom it is much harder for the electrons to move t hrough and thus the resistance will rise.So instead of just investigating how length affected the resistance of a piece of wire I could also have investigated the affect of temperature or cross sectional area on the piece of wire transport Burclaff Page 1 of 10 line of battle lagger only The above preview is unformatted text This student written piece of work is one of many that can be found in our GCSE electricity and Magnetism section.