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

Physics Investigation Of Resistance

Extracts from this document...

Introduction

Physics Investigation Of Resistance

Aim 1: To investigate how the electrical resistance of a wire changes in relationship to it’s length. Resistance is when these electrons which flow towards the positive collide with other atoms, they transfer some of their kinetic energy. This transfer on collision is what causes resistance.

Key factors: The factors in this experiment are

●The length of the wire

●The width of the wire

●The type of wire e.g. Nichrome

●The temperature of the wire

●The current passing through the wire

The factor I will be changing is the length of the wire, I will keep all the other factors the Same.

Prediction: I think that as the length of the wire increases so will the resistance of it. I also believe that the rate at which the resistance of the wire increases will be directly proportional to the length. I think this because electric current is the movement of electrons through a conductor. In this experiment a metal wire. So when resistance is high, conductivity is low. Metals conduct electricity well because the atoms in them do not hold on to their electrons very well. Free electrons are created, which carry a negative charge, ‘jump’ along the lines of atoms in a wire which are in a lattice structure. Resistance is when these electrons which flow towards the positive collide with other atoms, they transfer some of their kinetic energy. This transfer on collision is what causes resistance.

...read more.

Middle

R=V/I

Resitance (Ω) = Voltage (V) / current (I)

To calculate the resistance. My preliminary results are as follows.

Width (mm)

Resistance (Ω)

0.27

0.70

0.32

1.42

0.46

2.15

0.56

2.94

0.71

3.68

These indicate that if you increase the width of wire, the resistance increases. As you can see I have taken 5 well space results to give me an accurate perception of the relationship between a width of wire and resistance. To ensure I get an accurate set of results I will always measure the wire exactly.

Results:

This is not a very dangerous experiment but despite this we always handled electricity with care, we kept the current low, handled with dry hands etc.

To calculate my results accurately I have taken three readings for each length of wire and the used the equation

R=V/I

Resitance (Ω) = Voltage (V) / current (I)

to calculate the resistance.

Below is a graph to show my results when investigating how length of a piece of wire effects resistance

Current (amps)

Length (Cm)

Attempt 1 (volts)

Attempt 2 (volts)

Attempt 3 (volts)

Average (volts)

Resistance (ohms)

0.5

20

0.73

0.76

0.75

0.75

1.50

0.5

40

1.46

1.44

1.49

1.46

2.92

0.5

60

2.16

2.13

2.18

2.16

4.32

0.5

80

2.84

2.84

2.92

2.87

5.74

0.5

100

3.57

3.54

3.55

3.55

7.10

...read more.

Conclusion

I do not think that doing any more results in our experiment would have made it any more accurate. I feel that the only way to make it more accurate would be to use a different method – perhaps were we had a bar that did not bend in place of the wire. We could even use a rheostat in place of the wire, because it is essentially a long coiled wire that is connected at different lengths to change the resistance of the circuit

I will now evaluate my width experiments results.

I don’t think these results were as accurate as they could have been due to the fact that the width of each piece of wire did not vary in any regular pattern. This can be seen by the results in my graph. Also again slight variations in temperature and inaccuracy’s in the equipment could have effected my results . Also the wire not always being perfectly straight could effect my results. To improve this experiment further I could get different width’s of wire that follow a patter for example the width is doubled each time. I think it would be a good idea to use a bar or a rheostat.

...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

    Resistance Aim: my main aim is to investigate the factors that affect the resistance ...

    3 star(s)

    8 ohm rated at 5 A Safety Some components may become hot enough to burn fingers. Procedure a Set up the circuit as shown below. The potential difference across the lamp will be shown on the voltmeter or millimeter, set to volts and placed across the lamp as shown and the current on the ammeter.

  2. An in Investigation into the Resistance of a Wire.

    So it reduces the probability of having errors. * Redo the experiment but this time has more lengths maybe going up in 2cm instead of 5cm or investigate in more lengths say go up 200cm instead of 100cm. * I could have measured my lengths even more accurately by repeating it again, so three times instead of two times.

  1. GCSE Physics Resistance of a Wire

    Although it would be easy to obtain and record the data the graphs that I would be able to draw up would not be interesting. For the temperature of the wire I would not be able to carry out a fair test because it is extremely difficult to produce and control the range of temperatures needed without the correct equipment.

  2. To investigate the affect of wire width on electric current and resistance.

    We measured the voltage of each test on the voltmeter, and the amps produced on the ammeter. The measurements were then recorded. The wire was allowed 15 seconds between each test to allow it to cool fully before testing again.

  1. Resistance of a Wire Investigation

    false whereas a digital voltmeter does not rely on a needle or any other manual movements. The next modification I would make would be to use pointers instead of crocodile clips ; I would do this because pointers would be more accurate.

  2. How does length and width affect resistance

    This increases the amount of collisions therefore there is more resistance. However it is hard to keep the temperature exactly the same as the room temperature might change from day to day. It is essential to use a low voltage because it means a low current that will not heat up the wires.

  1. Resistance in a Wire Investigation

    The main two I can think of are stated below : "h Do not carry out the experiment in wet areas, as water is a very good conductor, and thus could be very dangerous.

  2. --- PHYSICS INVESTIGATION ---

    me enough results to plot an accurate graph and comment on it. DEPENDENT VARIABLE: will be the resistance as this really depends upon the length, material of wire, temperature and also thickness of the wire. Resistance involves collisions of the current-carrying charged particles with fixed particles that make up the structure of the conductors.

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