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

Factors Affecting The Resistance (Thickness)

Extracts from this document...

Introduction

Investigating the factors affecting the resistance

Name: Sukhdev Singh Shah

Form: 10GK

Introduction:

Resistance:

Electrons move more easily through some conductors when a potential difference is applied. Resistance is determined by how good or bad a conductor a material is.

A good conductor has a low resistance while a poor conductor has a high resistance.

OHM Ω

Resistance is defined by: R= V/I                 

If I= 2A when V= 12v, then R= 12/2 = 6 Ω

Resistors:

Some conductors are made from carbon or alloy wires, and are intended to have resistance, so we call them resistors. Resistors used in everyday life have values ranging form usually a few ohms, but go up to millions of ohms.

Resistors in a series:

The resistors below are in Series. The current flowing through all (I) is the same, and the separate potential difference across then is the same as the total potential difference across the 3 (V).

i.e. V= V1 + V2 + V3

If R is the combined resistance, V= IR

Resistors in parallel:

The resistors below are parallel. The total current (I) equals the sum of the currents in the separate branches, and the potential difference between the ends of each is the same.

i.e.

...read more.

Middle

image06.png

                A.C Power Pack                                                        Variable Resistor

Circuit Diagram:image00.png

image00.png

Method:

  • I will set up the circuit as shown above.
  • I will connect in a series circuit with an A.C. power supply, setting the value to an appropriate voltage.
  • I will then connect a wire which has a thickness of 26cm to the output from the ammeter.
  • I will then connect the voltmeter across the wire I am testing.
  • I will then connect the negative terminal of the voltmeter to the negative terminal of the power supply, therefore completing the circuit.
  • I will repeat the above process for all the required thicknesses of wires that are going to be experimented.
  • Because the thinner wires become quite hot, the readings must be taken quickly, but I will allow the wire to cool down before the next reading.
  • I will repeat the whole experiment again, this time starting off at the thickest wire and going down to the thinnest.
  • I will then record the resistance for each thickness of wire after the wire had been disconnected from the circuit.

Prediction:

I think as you increase the thickness of the wire, you also increase the amount of resistance.

...read more.

Conclusion

The resistance of a wire depends on the number of collisions the electrons have with the atoms of the material, so if there is a larger number of atoms there will be a larger number of collisions which will increase the resistance of the wire. If a certain thickness of wire contains a certain number of atoms when that thickness is increased the number of atoms will also increase.

Evaluation:

I enjoyed carrying out this investigation. I didn’t come across any problems while trying to set up the circuit. Everything was done correct and I got no anomalous results when I took the readings. These results aren’t very accurate because I only took one reading for each length of wire. If I had taken two or three readings for each length, then I could have found the average. This would have been more accurate. If I did this experiment again then I would use a resistor rather than a variable resistor because the results are unreliable. They are unreliable because everyone would have different results due to how they set up the resistance on the variable resistor.

Sukhdev Singh Shah 10GK                28/04/03

...read more.

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

    The factors affecting the resistance of a metalic conductor.

    4 star(s)

    Which leads us to conclude that the resistance of the wire is proportional to the temperature. The graph below shows this: MATERIAL: The fourth factor is the conductivity of the material we are using. Some metals are just more electrically conductive than others.

  2. Discover the factors affecting resistance in a conductor.

    Ohm's Law is a set of formulas used in electronics to calculate an unknown amount of current, voltage or resistance. I was named after the German physicist George Simon Ohm, who was born in 1787, and died in 1854. Ohms Law is defined as: "The amount of current flowing in

  1. Factors Affecting the Efficiency of a Wind Turbine

    The temperature didn't fluctuate but it should be noted that the thermometer used was less sensitive and measured to one decimal place only.

  2. Investigate one or more factors affecting the resistance of metal wires

    This will cause a lower resistance because of the increase of the number of electrons. If the particles in the material are tightly packed together, then there will be more collisions and therefore more resistance. Some conductors are better than others. Copper is a better conductor of electricity than iron.

  1. Investigation into the factors affecting the resistance of wire

    If the results are accurate then all the calculations done on the copper wires should be the same because the material is the same. As is shown, the majority of the copper wires have a material resistivity of around 2x10-5.

  2. An investigation into the factors affecting the resistance of a wire.

    E.G the filament across a bulb is quite thin, as it needs to resist the flow of particles for the bulb to glow (with a thin wire there will be more collisions between the electrons and the atoms as there will be less space to move).

  1. An investigation of the factors affecting the output of a transformer.

    In this case because the electrons in the secondary coil are in less contact with the field lines they therefore receive less energy. However because all the energy 'must' go through to the second coil and so the number of electrons (the current) increases. ( Power = current x time)

  2. Investigating the factors affecting the current flowing through a wire.

    There will be more resistance in a thinner wire as there are fewer charges (e-) passing a point per unit volume per second. Therefore there will be a lower current and a higher resistance. This is shown in the diagram below. There will be less resistance in a thicker wire.

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