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

Does a Light Bulb Obey Ohm's Law?

Extracts from this document...


Does a Light Bulb Obey Ohm's Law? Obtaining Table of Results Voltage 1 Current 1 Voltage 2 Current 2 Average Voltage Average Current Average Resistance 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.5 0.37 0.5 0.38 0.5 0.375 1.33 1.0 0.56 1.0 0.55 1.0 0.555 1.80 1.5 0.63 1.5 0.64 1.5 0.635 2.36 2.0 0.72 2.0 0.72 2.0 0.72 2.78 2.5 0.75 2.5 0.74 2.5 0.745 3.36 3.0 0.85 3.0 0.86 3.0 0.855 3.51 3.5 0.90 3.5 0.91 3.5 0.905 3.87 4.0 0.98 4.0 0.99 4.0 0.985 4.06 4.5 1.04 4.5 1.04 4.5 1.04 4.33 5.0 1.09 5.0 1.10 5.0 1.095 4.57 5.5 1.17 5.5 1.17 5.5 1.17 4.70 6.0 1.23 6.0 1.24 6.0 1.235 4.86 6.5 1.27 6.5 1.27 6.5 1.27 5.12 7.0 1.30 7.0 1.31 7.0 1.305 5.36 7.5 1.39 7.5 1.39 7.5 1.39 5.40 8.0 1.42 8.0 1.43 8.0 1.425 5.61 8.5 1.45 8.5 1.46 8.5 1.455 5.84 9.0 1.48 9.0 1.48 9.0 1.48 6.08 9.5 1.56 9.5 1.57 9.5 1.565 6.07 10.0 1.59 10.0 1.60 10.0 1.595 6.27 10.5 1.62 10.5 1.63 ...read more.


The smaller the cross section of a wire, the more struggle for electrons to go past, the greater the resistance * Wire Material. Different materials conduct electricity in different ways, the better the conductor, the less the resistance. The worse the conductor, the more resistance. * The same light bulb, which had the same tungsten filament. Ohm's law does not apply to circuits where there are temperature changes. The variable, temperature, meant that ohm's law could not be applied to the light bulb. It is the light bulb itself that emits the heat. It's source is the tungsten filament, as when electrons try to pass through the tungsten filament they collide with the tungsten atoms which induce heat and increase the atoms' vibration, which leads to further collisions and leads to more light heat and of course resistance. The result supports my Hypothesis. Evaluation I believe the investigation was successful as the results produced agree with scientific knowledge. ...read more.


Voltage was supplied with an accurate variable d.c. supply. Current was measured using an accurate ammeter and voltage was measured with an accurate voltmeter. For further accuracy I conducted the experiment twice so I could work out the average. Both times the results were expected and were very similar. Therefore I believe that this investigation has sufficient evidence to support a conclusion that a bulb does not obey ohms law. A bulb is a non ohmic conductor. If I were to repeat the investigation I would improve it by * Using other conductors like lasers. * Made the length of the wire into a an independent variable * Made the cross section area of the wire into an independent variable * Made the material of the wire into an independent variable * Made the type of bulb into an independent variable Although I believe my investigation to be a success I believe if I were to make the improvements I said, I would have reliable results with an even stronger conclusion as a wider range of information would have been taken into account Ohm's Law 1 Stepney Green School 10548 ...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. Peer reviewed

    How does the power dissipated by a light bulb vary with voltage?

    5 star(s)

    0V - 6V (because my light bulb will be a 6V one) so I will use the one which is 0 - 20V d.c. It will be precise to 2 decimal places. Power pack - It will need to give out voltages of 0V - 6V (because my light bulb will be a 6V one).

  2. charles law

    Results All results have been given to 2 decimal places. The number of oscillations per second is known as the frequency (f) which is measured in hertz (Hz), one hertz = one oscillation per second. The time for one oscillation is called the periodic time (T).

  1. How does current vary with voltage in a light bulb?

    Putting the ammeter in the flow doesn't affect the flow. In amps a value that is smaller than an amp is called a Milliamp (MA) 1000 MA = 1amp History on Goerge Ohm Goerge Ohm devised the relation ship between voltage and current. This was; Resistance = Voltage (V)/Current (A)

  2. Choosing a light source

    The light can take some time to brighten up as the tungsten takes a bit of time to warm up. The light that is produced form the light bulb allows as to see when it is dark. The tungsten wire is very sensitive and if the bulb is drop or

  1. Ohm's Law Investigation

    This is now called a flow of charge. Having explained the nature of the flow of charge, resistance is simply how hard it is for the electric charge to flow through something. The higher the resistance, the more energy is used up just getting the current through the wire/conductor.

  2. Ohms Law.

    Resistance is proportional to the cross-section are of the wire given that the length and the material should be the same. * Longer wires will cause an increase in resistance because the electrons have to travel past more atoms and collisions between the electrons and the atoms are more likely then in shorter wires.

  1. Ohm's law.

    I shall use different lengths. The I shall repeat the experiment on different gauges of wires and possibly on wires made of different materials. Apparatus * Power Pack (DC) * Multimeter (x2) * Rheostat * Nickel Chromium Wires (x4... SWG 30, 28, 24,,22)

  2. A little bit about the life and times of Georg Simon Ohm:

    Resistivity The resistivity, symbol ? (one of the Greek alphabets pronounced rho), of a material is an important property since it relates the electrical resistance of a conductor to its physical size. i.e. it relates the resistance to the length and area of the conductor.

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