• 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)

    It would be not possible to get accurate length using this method. It was measured to top facility but the border of error could easily have been up to 1cm considering the poor means in which the wire was help in position, by crocodile clips.

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

    The percentage error is under 5.7%. But all of them are under 2.4% part form the 10cm length this could be that the length was very short and the wire may have started to heat up causing the resistance to be higher.

  1. GCSE Physics Resistance of a Wire

    If I chose to measure the difference in the resistance in different materials I would chose a number of different materials and using the same voltage I would record the resistance given by each wire of the same length and width.

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

    * 3 sets of 100cm constantan wire; thin medium, thick * Meter ruler Method: Before we conducted the experiment we checked that the area was clear of any hazardous objects, which could be a danger to us, or the experiment. We also ensured the desk was both dry, and clean.

  1. Resistance of a Wire Investigation

    SUPPLY 2 VOLTS AMMETER VOLTMETER WIRE METRE RULER Instead of connecting the voltmeter to the main circuit I would connect it to the wire which is being tested. I would do this so that the voltmeter is measuring the voltage of just the wire being tested and not the wires of the main circuit as well.

  2. Resistance in a Wire Investigation

    I started the experiment by sellotaping the Nichrome Wire (over 1 meter long) to the meter ruler. Then the multimeter was switched on which was connected to the Nichrome wire via the crocodile clips. The resistance was then recorded down for various lengths ranging from 0 �V 100cm.

  1. How does length and width affect resistance

    It is like letting a lot of water out of a small hole; it would go slowly, whereas with a bigger hole it flows out faster. Temperature of wire When the temperature of a metal increases the resistance of that metal increases.

  2. --- PHYSICS INVESTIGATION ---

    A resistor is a material that makes it hard for electrons to go through a circuit. Without resistance, the amount from even one volt would be infinite. Resistance occurs when electrons travelling along the wire collide with the atoms of the wire.

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