• 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

# An investigation into the factors which affect the electrical resistance of a length of wire.

Extracts from this document...

Introduction

An investigation into the factors which affect the electrical resistance of a length of wire

Planning

Aim

To find how the length of a wire affects its resistance.

Introduction

An investigation into the factors which affect the electrical resistance of a length of wire. This basically means that we are investigating if the length of a wire affects the resistance.

Some materials such as metals are good conductors of electricity because they have free electrons. All metals are good conductors of electricity in both there solid and liquid states. Solid ionic compounds are poor conductors of electricity. However when molten or in aqueous solution the crystal lattice is broken up and the ions are free to move.

Non metals do not have free electrons. Metals have free electrons. Free electrons are the outer shell electrons.

Drift velocity –

Metal

As you can see here I have given a example of one of the free electrons. You could imagine it is on all of the atoms.

As you can see here the electron is pointing to one direction only. You could imagine all of the other electrons on the atom are pointing the same way.

I have found by out by doing some research of my own by looking in a chemistry book

Middle

A flow of electrons causes a current. Resistance is caused by obstruction to the flow of charge (free electrons). If the metal is pure, crystal lattice is very regular. The electrons will then flow through easily because there will be lots of straight routes for the electrons to follow. If a positive ion gets in the way of an electron, then the electron will collide with the ion.

Variables

Factors which can change the resistance of wire:

1. length of wire
2. thickness of wire
3. temperature of wire

Prediction

Well I predict that, in the case where the length of the wire is varied, as the wire becomes longer the resistance of the wire increases. I also predict that the resistance is proportional to the length of wire. So as the length of the wire increases in equal steps, so does the resistance in equal steps. I predict this because if the length of wire increases there are more atoms so free electrons collide more. So the temperature increases so then resistance increases. Double the length, double the ions, double the electrons so double the resistants.

On this page I have input a diagram to make my prediction clearer.

Here I have input a diagram to specify what I am saying for my prediction:

Here you can see there is a smaller length of wire then of the opposite.

Conclusion

This was a successful experiment overall as me and my team worked well and hard at it to achieve the best possible grades. Although we have some difficulties at the start, but gradually as we paid more interest and got on with it my predictions matched up to the conclusion that it clearly showed the resistance was directly proportional to the length of the wire and inversely proportional to the cross sectional area of the wire.

I think the only way of improving our results and making our results more accurate is by using digitalised meters. As I said the procedure was not very accuracy because error due to instrument (systematic error) and human error (random error). If here is ant fault in calibration then that will be carried over to every measurement. A repeated result will make it more accurate.

Avoid parallax error- look from the top. I repeated 3 times and write down average and that’s how I reduced the error, hence: my results look very accurate to me.

Reliability- I kept all the variables same – THICKNESS and MATERIAL.  My repeated results appear to be the same; therefore my results must be reliable. If the wire gets hotter, the particles vibrate more, so the resistant increases. The temperature for the shorter length of the wire is more likely to be hotter.

I think I worked well in my group and I hope to do the very best.

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

# Related GCSE Electricity and Magnetism essays

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

3 star(s)

R x A is to some extent constant. And this supports my calculations that the thicker the wire, the lesser its resistance. This concludes that the resistance of a wire is inversely proportional to its thickness: R ? 1/A. This is because of the fact that the electrons flowing through the wire bump with other atoms of the wire.

2. ## An experiment to find the resistivity of nichrome

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

1. ## Resistance of a Wire Investigation

The only one that does not is the point at 90cm, which was exactly at the point that the black mark (mentioned previously) was found to be. Wire 2, on the other hand, had three main anomalous results: at 50, 80, and 90cm.

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

Step 5 Check that all the wires were connected properly to the other apparatus and then turn on the mains power and recorded the voltage and current for that length of that wire. Take 5 readings for each length of wire.

1. ## Discover the factors affecting resistance in a conductor.

0.09 0.09 0.09 48.12 8 4.32 4.32 4.32 0.12 0.12 0.12 36.06 6 4.30 4.26 4.28 0.16 0.16 0.16 26.82 4 4.30 4.27 4.29 0.14 0.14 0.14 30.61 2 4.29 4.26 4.28 0.18 0.18 0.18 23.80 Diameter 1.5 cm Length (cm) Voltage 1 (V) Voltage 2 (V) Voltage average (V)

2. ## How does the length and cross-sectional area of a wire affect resistance

This causes more collisions between the electrons and the atoms as the atoms are moving into the path of the electrons. This increase in collisions means that there will be an increase in resistance. * Material: The type of material will affect the amount of free electrons, which are able to flow through the wire.

1. ## To investigate how the length (mm) and the cross-sectional (mm2) area of a wire ...

I am only testing to see if there is a change in the variables. The results for my preliminary experiment are listed along with the results for the entire experiment. 2. OBTAINING EVIDENCE 2.1. Preliminary Results: The following results are all the values for current and voltage that I obtained while doing the preliminary experiment for length and cross-sectional area.

2. ## Investigation of the factors that affect the resistance of a wire.

o The crocodile clips will be attached to the wires at points 1 and 2; these will be used to connect one of the loose wires with the cross sectional area of 0.08 mm2 to the rest of the circuit.

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