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

How the Length of a Piece of Wire Can Affect the Resistance Within the Circuit.

Extracts from this document...


Physics Coursework


I am trying to find out how the length of a piece of wire can affect the resistance within the circuit.



With an energy source, such as a battery or a generator, the size of the current that flows is decided by the resistance of the circuit. The bigger the resistance within the circuit, the harder it becomes for electricity to flow through the circuit. The resistance within a circuit is measured in Ohms (Ω).

Structure of Metals





When a potential difference is applied, the electrons gain energy and this causes them to move in the same direction as the current. As electrons pass along, the metal, there will be collisions with the metal ions this causes the metal to heat up this is due to energy transfer in the collision. The electron flow of the current reduces when this happens.

...read more.



                          +                                                                          -image02.pngimage15.pngimage11.pngimage14.png






                                                                                    Sliding contact



This circuit diagram displays: 3 Batteries, 1 Rheostat (Variable Resistor), 1 piece of 100cm Nichrome wire, 1 Ammeter and 1 Voltmeter. The Voltmeter is connected across the Nichrome wire because it is measuring the potential difference between it’s ends; the + terminal is connected to the + side of the circuit.

  • Connect the circuit as shown in the diagram above.
  • Adjust Rheostat to different values i.e. 0.3A, 0.5A etc Do these readings for multiple wire lengths.
  • Record readings at the voltmeter, which records the voltage, and the ammeter, which records the current. These records will be stored in a table.
  • Draw a graph of results displaying the readings on the ammeter and the voltmeter.

Independent Variables: This is what I will change during the experiment, such as the length of wire.

Dependant Variables: This is what will change due to the “Independent Variables” such as the Resistance.

...read more.


W (V)

W (A)

W (Ω)


X (V)

X (A)

X (Ω)


Y (V)

Y (A)

Y (Ω)


Z (V)

Z (A)

Z (Ω)


This is a small example of what the table will be like. In the experiment I would continue to go up sequentially in tens until the length of wire reaches 90cm. I will then take another reading from where the length of wire remains the same but the rheostat will have been changed. The current throughout the experiment will remain the same. For safety reasons and to make this a fair test we have to let the Nichrome wire cool down before we test another length for resistance.

After I have completed two tables like the one shown above I will create a table with the average of the two resistances.

Resistance (table a)

Resistance (table b)

Average Resistance (Ω)

Wire Length (cm)

W (Ω)

W (Ω)

W (Ω)


X (Ω)

X (Ω)

X (Ω)


Y (Ω)

Y (Ω)

Y (Ω)


Z (Ω)

Z (Ω)

Z (Ω)


The information from the table will be put onto a graph:

Predicted Outcome

Average Resistance (Ω) in Ohms

                                                          Wire length (cm) in centimetres

...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. Find out how the length and width affect the resistance of a graphite track.

    by the ohmmeter. Having obtained these results they will be entered into a matrix. Graphs can then be drawn from this table. PRECAUTIONS AND SPECIAL TECHNIQUES For this experiment I decided to use card with grid lines photocopied onto it. Card is stronger than paper, so when being coloured upon I will not rip the card.

  2. How does length and width affect resistance

    WIDTH 1. chose a wire 2. Measure it on the micro-meter. a) Place the wire on the space in the micro-meter b) Using the small screw tighten it. c) Do not use the big one for thin wires as it can damage the micro-meter. d) The value it says on the micro-meter is the width of the wire.

  1. Physical - Circuit

    And the constantan wire with 5 centimetres was heating up, and it changes its colour from silver into golden red and very shiny. This is the first time and the last time this mistake happened in our experiments. By resetting up the circuit, we learned about how to use a variable resistor.

  2. How does the length of a piece of wire affect its resistance?

    Ohm's law states that a current flowing through a metal conductor is directly proportional to the voltage across its ends (provided all other conditions are constant). So I know that if we add a variable - in this case length - resistance will change.

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