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

Investigating Ohms Law.

Extracts from this document...


Christopher Prentis 11OW                Physics Plan

Introduction: In this experiment, we will be investigating Ohms Law and we will be doing this by testing the potential difference across a wire.  The ohm law is R=I/V

Where R = resistance

I = current

V = Voltage

I predict that the factors that can affect the potential difference of the wire are:

  • Length of wire
  • Thickness of wire
  • Temperature
  • Type of material

Ohm’s Law which states “The amount of current flowing in a circuit made up of pure resistances is directly proportional to the electromotive forces impressed on the circuit and inversely proportional to the total resistance of the circuit.” It is measured in (Ω) and the equation used is:

Resistivity Ω =  Voltage V


 Current A

I think the length of the wire is directly proportional to resistance.

...read more.


Apparatus: Cell                        Volt meter

              Nichrome wires                Ruler

              Crocodile clips

Safety: To make this experiment safe, I will not short circuit the battery, and also I will check the circuit before completing it.


  • Take a 2V cell and connect it to wire 1 at point A on the above diagram using crocodile clips.
  • Measure the length of wire 1 using the ruler
  • Connect wire 1 to wire 2 at point B on the above diagram using crocodile clips
  • Attach wire 2 to the cell at point C on the above diagram again using crocodile clips
  • Attach the volt meter to points B and C
  • Note the reading of the meter on the table below
  • Change the length of wire 1 and reattach the wire into the circuit
  • Note down the new length and new voltage
  • Repeat the above steps for at least 10 times, to obtain a more accurate set of results for drawing the graph
  • Draw a graph and plot the results obtained using the results table below.
...read more.





















As you can see from above, the results I obtained prove that the prediction I gave was correct.

Graph:  See attached sheet


The experiment went well, but I think that I could improve the experiment by having a more sensitive voltmeter and also by having a more powerful cell.  From the results I have acquired, I was able to produce a reliable conclusion, which supports my theory in my prediction that as the length of the wire increases, the potential difference increases, and so does the resistance.  I think my results are fairly reliable, as they are closely correlated to the line of best fit I have drawn. Also my graph proves that the results had little flaws due to the line of best fit and they also confirm my predictions.

...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. Resistance Of a Wire - Ohm's law.

    Therefore, more energy is going to be lost in these collisions (as heat). * Furthermore, doubling the length of the wire will result in double the resistance. This is because by doubling the length of the wire one is also doubling the collisions that will occur, thus doubling the amount of energy lost in these collisions.

  2. Ohms Law.

    This means that the current is proportional to the p.d. The relationship is called Ohm's law. Ohm's law only applies if the temperature is constant, and does not apply to all electrical components. We can write Ohm's law in symbols: V ??I Or V = IR And R is the resistance of the resistor.

  1. Ohm's law.

    This process shall be repeated until the whole length of the wire has been covered then the same test shall be done on a different wire. Once the whole wire has been tested, the crocodile clips shall be placed 1mm apart on a section of the wire.

  2. To measure resistance and verify ohms law

    One of the reasons copper is used in wiring is because it is a good conductor. When the temperature is increased the resistance will also increase. This is because the particles in the object will start to move around faster.

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