• 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
  12. 12
    12
  13. 13
    13

Investigation on the Resistance of Nichrome wire

Extracts from this document...

Introduction

Lucy Kennington C2

Investigation on the Resistance of Nichrome wire

Planning

Variables

  • Voltage
  • Current
  • Length of wire
  • Apparatus used in the circuit
  • Temperature of room
  • Thickness of wire
  • Temperature of wire
  • Material that the wire is made from

Investigating how changing the length of Nichrome wire affects the resistance

Apparatus

  • 1000mm Nichrome wire
  • 2 leads
  • 2 Crocodile Clips
  • Multimeter (Battery operated)
  • 1000mm Ruler
  • Thermometer
  • Sellotape



Preliminary experiments

I carried out a preliminary experiment to find out which apparatus would be best suited to find the resistance of Nichrome wire, to see the other factors that could affect the experiment and also to see if I could improve any of the steps in the method.

I began by setting up two circuits, the first with a multimeter and the second with a power pack, I wanted to see which one would be more accurate for my investigation. Using a multimeter is more accurate because it keeps the current going through the circuit low which keeps the temperature of the wire just about the same, this means if the wire is not heated and so the particles of atoms and electrons will not collide as frequently which therefore will not convert as much kinetic energy into heat which could affect the results. The multimeter will have the same current because of the fuse, the fuse only lets up to 0.25A flow through any circuit, this is a low current so it will not give the wire a noticeable heating affect although there is very little temperature change, but it would not affect my investigation.

If I used the power pack to find the resistance of the wire I would have to wait for the wire to cool down in between each

...read more.

Middle

As the cross-sectional area of the wire doubles, the resistance will half. There would be twice as many ions and twice as many electrons bumping into them, but also twice as many electrons getting through twice as many gaps. If there are twice as many electrons getting through, there is twice the current, the resistance must have halved. The thinner the wire is the less channels of electrons in the wire for current to flow, so the energy is not spread out as much, so the resistance will be higher: We see that if the area of the wire doubles, so does the number of possible routes for the current to flow down, therefore the energy is twice as spread out, so resistance might halve.

I think the graph will be like the shape I have drawn it because I predict the longer the wire the higher the resistance and because I think the resistance of wire will go up by the same amount each time. I think the graph will be straight in a diagonal line going to the right. The graph line does not go through the origin because even if I were to place the crocodile clips on the wire at 0mm there would still be a resistance because of the resistance of the leads. The graph would go through the origin if I took away the resistance of the leads and the crocodile clips, this would not give an accurate drawing of the graph though because when the crocodile clips are touching and connected in the circuit with the multimeter there will always be some resistance due to the leads.

Bibliography

(1) = Internet resources

Table of Experiment Results

Length of Wire (mm)

Thickness of Wire (mm)

Room Temp (˚C)

Voltage (V)

Current (A)

Resistance of Wire (ohms)

1

2

3

0-0

0.45

21

9

<0.25

0.3

0.3

0.3

0-100

0.45

21

9

<0.25

1.0

1.0

1.0

0-200

0.45

21

9

<0.25

1.7

1.8

1.7

0-300

0.45

21

9

<0.25

2.4

2.4

2.5

0-400

0.45

21

9

<0.25

3.2

3.1

3.2

0-500

0.45

21

9

<0.25

3.9

3.9

3.9

0-600

0.45

21

9

<0.25

4.6

4.6

4.8

0-700

0.45

21

9

<0.25

5.3

5.3

5.3

0-800

0.45

21

9

<0.25

6.0

6.0

6.1

0-900

0.45

21

9

<0.25

6.9

6.7

6.7

0-1000

0.45

21

9

<0.25

7.4

7.4

7.5

...read more.

Conclusion

I think I got those anomalies because of a wrong measurement when I was attaching the crocodile clip to the wire. I probably just made the increasing gap bigger than it should have been because the resistance between the two points were more than normal 0.7ohms.

If I had time the additional experiments which I would have carried out to be sure of my graph results would be longer length of Nichrome wire, to see if the graph would carry on in a straight line and increase by the same resistance each time and the resistance of the clips and leads would have been less significant.

I do not think there is another way to investigate the variable I did apart from changing the apparatus and using a power pack, digital voltmeter and ammeter instead of using a multimeter.

Things, which could affect the end result of my investigation, need investigating. Things that could affect my final results would be rusty old crocodile clips so I would have to test them to make sure they gave the correct resistance. I could do this by attaching two crocodile clips together in a circuit with a multimeter and if the resistance were different from 0.3ohms I would know that they are not giving me the correct resistance. I know this because in my preliminary experiment I did the same but with clean crocodile clips and they gave me a resistance of 0.3ohms. If I were using a power pack I would also need to investigate the heating affect. I would have to use a thermometer to check the temperature of the wire.

G.C.S.E Science Coursework

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

    As done in the previous Analysis section, we calculated our results, and analyzed our graphs so that I could implement certain formulae into the experiment that would back up my conclusion. Please review the Initial research. Safety To ensure that the experiments where safe, there were certain precautions that had to be observed.

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

    I= current in amperes (A) R= resistance of the circuit (?) The resistance of a wire will depend on it shape and size. The longer the wire is the greater the resistance so the smaller the wire the smaller the resistance will be, provided that the wire is the same thickness and material.

  1. Investigating how the resistance of Nichrome wire depends on its length

    Variable Power Supply A power supply (sometimes known as a power supply unit or PSU) is a device or system that supplies electrical or other types of energy to an output load or group of loads. The term is most commonly applied to electrical energy supplies.

  2. Does Increasing the Length of a Nichrome Wire affect its Resistance

    = Current (Amps) * Voltage (Volts). In order for me to do it 5 times I will place the Variable Resister at different positions to give me different readings for Current and Voltage each time for each length of wire. I will keep the temperature, thickness of the wire and also the amount of volts on

  1. How does the resistance of Nichrome wire change as its length changes?

    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. Safe Test 1. To make our test a safe test we knew that we couldn't

  2. Resistance of a Wire Investigation

    Crocodile clips �V To connect the wire being investigated to the rest of the circuit. * Voltmeter & Ammeter �V To measure the resistance. * Wires �V To connect the above items and to complete the circuit. * To measure the resistance of the wire I am going to use

  1. An experiment to find the resistivity of nichrome

    120cm 1.7 1.8 1.6 1.6 1.7 2.9 150cm 1.3 1.2 1.4 1.4 1.3 3.8 The two tables above show the results given in the preliminary experiments they both seemed to heat up the wire to a substantial heat proven by the red glow on the 30cm wire (occasionally).

  2. The resistance of wire.

    The equation for resistance = V/I Results SWG (thickness/mm) Voltage/volts Current/amps V/I=R/ohms Average R/ohms Thickness investigation (Length kept constant at 15cms) Graph 1 - relationship between the wire's thickness and its resistance wwff ffw esffffs ayff ffba nff kcff ffuk.

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