• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month
Page
  1. 1
    1
  2. 2
    2
  3. 3
    3
  4. 4
    4
  5. 5
    5
  6. 6
    6
  7. 7
    7
  8. 8
    8
  9. 9
    9
  10. 10
    10
  11. 11
    11

Factors affecting the resistance of a wire

Extracts from this document...

Introduction

RESISTANCE OF A WIRE INVESTIGATION

Skill Area P; Planning Experimental Procedure

Hypothesis

Four factors affecting the resistance of a wire are:

·  The temperature of the wire.  If the wire is hotter than usual then electrons are given more energy and collision is more frequent.  Therefore the resistance is greater.

·  The length of the wire.  The length of the wire is directly proportional to the resistance and so if the length of the wire is longer, then the resistance of the wire is greater.

·  The width of the wire.  Thick wires have more free electrons per unit cross-sectional area than thin wires.  Therefore thicker wires will have a larger resistance than thinner wires

·  The metal that the wire is made out of.  Some metals conduct heat easier and quicker than others.  All metals are good conductors because there are lots of free electrons to move between the atoms of the metal.

Prediction

If the length of the wire is doubled, then the resistance will double.  This means that the resistance is proportional to the length of the wire.

As the length of the wire is increased, there are more atoms present for electrons to collide with and therefore resistance is greater.  More and more atoms can also collide and collisions become more imminent.  There are more and more free electrons and when the electrons collide with atoms, energy is transferred to the atoms that start to vibrate and the material becomes hotter.

...read more.

Middle

90.0

0.40

3.64

9.10

90.0

0.50

4.53

9.06

90.0

0.60

5.46

9.10

Average Resistance:

9.04

Length of a wire (centimetres)

Current I (Amperes)

Voltage V (volts)

Resistance R=V/I (ohms)

80.0

0.20

1.59

7.95

80.0

0.30

2.43

8.10

80.0

0.40

3.25

8.13

80.0

0.50

4.05

8.10

80.0

0.60

4.88

8.13

Average Resistance:

8.08

Length of a wire (centimetres)

Current I (Amperes)

Voltage V (volts)

Resistance R=V/I (ohms)

70.0

0.20

1.42

7.10

70.0

0.30

2.15

7.17

70.0

0.40

2.87

7.18

70.0

0.50

3.57

7.14

70.0

0.60

4.30

7.17

Average Resistance:

7.15

Length of a wire (centimetres)

Current I (Amperes)

Voltage V (volts)

Resistance R=V/I (ohms)

60.0

0.20

1.20

6.00

60.0

0.30

1.81

6.03

60.0

0.40

2.44

6.10

60.0

0.50

3.05

6.10

60.0

0.60

3.65

6.08

Average Resistance:

6.06

Length of a wire (centimetres)

Current I (Amperes)

Voltage V (volts)

Resistance R=V/I (ohms)

50.0

0.20

0.99

4.95

50.0

0.30

1.50

5.00

50.0

0.40

2.04

5.10

50.0

0.50

2.53

5.06

50.0

0.60

3.07

5.12

...read more.

Conclusion

Anomalous Readings

There are no anomalous readings in my results.  All my results are touching or very close to the line of best fit.  This just shows how successful my experiment actually was.  However if there were anomalous readings then I would have identified them on my graph and tables as anomalous.

Improving the Accuracy of the Readings

My readings are very accurate, however if I wanted to make them even more accurate I could use a digital ammeter rather than an analogue ammeter that I used in my experiment.  This way I could simply read the current and the readings would probably be to 2 decimal places.  Therefore my results would be much more accurate.

Improving the Reliability of the Evidence

To improve the reliability of my readings I could have repeated the experiment more times.  Also, I could have even used a much more higher scale with the length of wire such as 10cm to 300cm.  We could also use a data logger to measure readings.  Data loggers are much more accurate as they measure digitally through a computer.  We could also use improved contacts on wire; so we don’t have any rusty wires etc.  We could also use intervals of 5 centimetres to get twice as many points on the graph.

Kai Baker

10 Alpha

Physics Coursework

Mr O’Malley

...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)

    Each slope represents the various thickness' of wires I used ranging from 0.4mm to 0.91mm. The 0.4mm wire has the least steep slope, and we say that it has highest resistance, whereas the 0.91mm wire line has the steepest slope and thus we say it has the lowest resistance.

  2. Factors Affecting the Efficiency of a Wind Turbine

    It was included to test if any round shape can generate good results. It was a control experiment. Apparatus Everything mentioned in the first experiment will be used except for an oscilloscope. A digital multi-meter will be used instead of an oscilloscope.

  1. Physics GCSE Coursework:Factors affecting the resistance of a wire

    Meter Ruler Method: In my experiment I have chosen that I will use wires with different SWGs but with the same length of 50cm. I chose 50cm because it has a normal average resistance, which is not an extreme high or an extreme low, and so the results would be fairly normal.

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

    Different materials have different resistance depending on the materials' atomic structure (composition). The type of material affects the amount of free electrons there are. The number of free electrons depends on the amount of electrons in the outer shell of the atoms.

  1. Discover the factors affecting resistance in a conductor.

    As mentioned, when the voltmeter/ammeter method is being used, a power-pack will be needed, keeping the power levels constant. My results showed that when the length increased, the resistance increased to show that they are directly proportional. I hope to see a very similar trend of results when I perform

  2. Factors affecting Resistance of a wire

    The reason for these collisions is that in a longer piece of wire, there are more free electrons in the actual atoms of the wire that can carry electricity. When there is an electric field the loose electrons escape towards the positive charge (opposites attract).

  1. Investigating the factors affecting the resistance in a wire

    of amperes (A), V is the potential difference measured across the conductor in units of volts (V) and R is the resistance of the conductor in units of ohms (?). In circuits, three equivalent expressions of Ohm's Law can be used interchangeably: The interchangeability of the equation may be represented be a triangle (see Figure 4), where V (voltage)

  2. An Investigation into the Factors Affecting the Resistance of a Wire.

    Since resistors in series just add up, the total resistance of this combination is 2R. The same thinking can be applied to a 0.3m length which will have a total resistance of 3R. Doubling the length of the wire, doubles the resistance.

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