• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Science Investigation Into What Affects The Resistance Of A Wire

Extracts from this document...


Science Investigation Into What Affects The Resistance Of A Wire By Owain Bristow 10E3 I am investigating what factors will affect how much resistance a wire will give to a current of electricity passed through it. Possible factors I could investigate are: * Length of the wire. * Cross sectional area of the wire. * Material the wire is constructed from. * Tension of wire. * Temperature of the wire. * Amount of current passed through wire/ amount of voltage. * Light shining on wire. I have chosen to investigate the length of the wire used in my experiments, because it is one of the easier ones to do with the equipment available to me and will produce a line graph. Doing a material investigation would yield a bar chart so would not give a complete explanation, it would be quite hard to alter the wire's temperature or try and investigate the effect of light. Changing a wire's tension would also make it thinner and so alter its surface area. I already know by Ohm's Law that in a fixed length and thickness of metal with a constant temperature the current is directly proportional to the potential difference so the resistance is always the same, with it equalling V/I. ...read more.


All my measurements will be given correct to two significant figures. Safety To be safe I will use a low voltage during my experiments so that the wire is not burnt (and neither am I) and no equipment is damaged. I will not to electrocute myself, turning the power on after I have let go of the wire. I will make sure I do not short circuit anything. Between experiments I will keep the power pack switched off. Results Length Of Wire Investigation Length of wire (cm) Current1 (A) Current 2 (A) Current 3 (A) Average Current (A) 1/current (A-�) Resistance-2/I (?) 5 2.80 2.60 2.47 2.62 0.382 0.763 10 2.00 2.00 1.85 1.95 0.513 1.03 15 1.45 1.60 1.60 1.55 0.645 1.29 20 1.20 1.40 1.35 1.32 0.758 1.52 25 1.10 1.15 1.10 1.12 0.893 1.79 30 1.00 1.00 0.90 0.967 1.03 2.07 35 0.850 0.850 0.850 0.850 1.18 2.35 40 0.750 0.800 0.700 0.750 1.33 2.67 45 0.700 0.700 0.650 0.683 1.46 2.93 50 0.600 0.600 0.600 0.600 1.67 3.33 Conclusions My graph of 1/current against wire length shows that the relationship between the amount of current and the length of wire is inversely proportional, as the wire gets longer less current is able to flow through it. ...read more.


To get more evidence to support my conclusion I could try the experiment at a different voltage, or keep the current constant or use a different material wire, to see if the results are similar to my present results. To extend this investigation further I could also investigate the cross sectional the wire and how this would affect its resistance. I could then with the results of both investigations find out whether there is a connection between the length of the wire, its cross sectional surface area and its resistance. I could also investigate the other possible factors such as temperature of wire and materials, with different numbers of free electrons, to find how they affect the resistance and if so, do the results obtained show similar patterns to the length investigation. According to Physics by Robert Hutchings and other A-Level textbooks the length L, cross sectional surface area A and resistance R of a wire are linked by the formula: ?=RA L Where ? is the resistivity constant of the material in Ohm metres, R is in Ohms, A is in square metres and L is in metres. Therefore I can check the accuracy of my results by substituting the values I obtained into the formula to see if the answer matches the actual resistivity of the metal constantan quoted in the book to be 49 x 10 ...read more.

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.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related GCSE Electricity and Magnetism essays

  1. Resistance of a Wire Investigation

    Turn on the power and set the power pack to read 0.2 volts. Take the current reading then turn off the power and start again. Take four readings like this so that an average resistance can be found. Next, change the thickness of the wire and do the experiment again.

  2. An in Investigation into the Resistance of a Wire.

    So because E26 has the largest cross-sectional area out of the six this would mean that it has a lower resistance than the other five wires. In the table it also shows that cross sectional area is inversely proportional to the resistance because if you half the cross sectional area you double the resistance.


    However, an ammeter ranging from 0 - 2A could be used instead; this though is not as accurate as the 0 - 1A ammeter as its scale ranges in intervals of 0.2A. Lowering the voltage on the power pack does/may not affect the resistance when worked out using the formula Resistance (R)

  2. An investigation into what affects the resistance of wire

    This is the wire I will be investigating the resistance. All the components will be connected in a line, end to end. It is in a series, so if one component get disconnected, the circuit is broken and other component will stop working.

  1. Resistance Investigation

    When two or more resistances are in series in a circuit, the total resistance may be calculated by adding the values of such resistances. If the resistances are in parallel, the total value of the resistance in the circuit is given by the formula: In a parallel circuit, electrical devices,

  2. To investigate how current affects the resistivity of a wire.

    and also wasn't too low either. This gave me good results and therefore I've decided to use it in the real experiment Apparatus: 2 circuit wires 1 metal wire 2m in length (Nichrome wire 285WG) A Power pack An Analogue ammeter 2 crocodile clips 1 meter ruler Method: First I will get all the equipment listed

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work