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

How variables effect the Resistance of a Wire.

Extracts from this document...


How variables effect the Resistance of a Wire My aim is to explain how current flows through a wire and also to explain how different things can effect the resistance. I will be collecting data to see the resistance when the length or diameter of a wire is changed. An electric current is made up of thousands of electrons passing through a wire. Everything is made up of tiny particles. Some of these particles are called electrons and can move when there is an electrical current. The more electrons that are flowing, the larger the current. Current is measured in Amperes (or Amps) this is shown as A. As electrons flow through a wire they pump into atoms in the wire. Electrons only flow when given electrical energy. Energy is often given through an electrical cell or battery. If the cell is a complete circuit the electrons are pushed out of one end of the cell round the circuit to the other end. The size of the push is called the potential difference or voltage. The bigger the pd the bigger the current that will flow around the circuit. Voltage is measured in Volts (V). Resistance is how difficult it is for current to flow through something. ...read more.


The following data is the result from the real experiment. For the experiment I will connect a piece of nicrome wire with a swag of 26 to a meter ruler. I will connect the wire to clips connected to the power pact. The power pack will provide a voltage of 3 Amps. There will be an ammeter connected to the wire to measure current. I need to know the current so I can use V=IxR to work out the resistance. I will take 5 readings at each length to insure data collected is accurate and I can see a trend and delete anomalies if the occur. I will measure in 10cm intervals so we can see a pattern. It would be harder to see a pattern otherwise. If we did it at larger intervals (eg. 20cms) there wouldn't be enough room on the ruler to carry out as many different lengths as possible. For example, with 10cm intervals we can measure 10 different lengths but with 20cm intervals we could only measure 5. We use nicrome because there is a large stock available and it is the same as the one I used in the trial test on the computer so we are able to compare. We use 3 volts because if it was any higher the wire would start getting hot and would cause more resistance the longer it was turned on. ...read more.


If I were to do this again I would make sure I did all of the experiment on one day. I would do this because I may not have gotten the same wire and ruler as I used for the experiment the day before. This would be a problem because one wire may be more bent or curly causing the wire to be longer than is seams. This would make my data more reliable and be more accurate. I think for the purpose of my experiment that I did enough trials and can be sure that my information is correct. However if I were studying for important information at a University level or even a college level then a lot more than five trials would be needed to obtain sufficient evidence. I could have tried my experiment on different days to insure unusual circumstances that I have no control over didn't effect my results. Another way in which I could go about investigating how variables effect the resistance of a wire is to change the diameter or temperature of the wire while applying an electric current. As you change the diameter the resistance would increase with the thinner the wire becomes because there would be less room for the current to flow through. As the wire becomes hotter I think the resistance would also increase because the particles in the wire heat up and move around making it hard for the current to move through. ...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. Marked by a teacher

    An Investigation To See How Resistance Can Be Changed By Variables.

    4 star(s)

    I will have to look out for gaps in my circuit because if the circuit is not complete the reading will become very high and not change, this would give me odd results and would have to be corrected in order to keep all the data consistent.

  2. Questions and answers on the 'Photoelectric Effect'.

    This is known as the "Motion of the Holes". The doped semi-conductor described above is called a P-Type semi-conductor. Now when the two types of semi-conductors are combined in a p-n junction, electrical energy can be produced. In the N-Type there are many electrons (from the phosphorus atoms, having 5 electrons)

  1. The effects on resistance with the variables of length and thickness.

    > Set the voltage quite low, like four because you don't want the wire to get too hot, as it would effect the resistance. This also happened in my preliminary experiment, at high voltages the wire became hot and the resistance increased, decreasing the reliability of my results > First, using Nicrome wire cut it six times at different lengths.

  2. The Photoelectric Effect

    Let's look back at the case of the zinc plate at the start of this section. The photons arrive and interact with (hit !) electrons in the metal. Now here's a useful rule to follow. Each photon only interacts with one electron.

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