• 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

# An investigation of the factors that affect the resistance of a wire

Extracts from this document...

Introduction

## An investigation of the factors that affect the resistance of a wire

Plan

Metals conduct electricity because the electrons in the metal can move about
inside the structure.
Wires can be made of different metals - and the reason why they give different resistances is all down to the number of  “free” electrons there are in that metal - these are electrons that aren‘t involved in bonding, and are “left over”. Current, is the flow of electrons around a circuit. Those materials, which have a lot of “free” electrons, will make it a lot easier for current to flow through, and so there is low resistance. That‘s why not all metals are equally as good at
conducting electricity.

The other things that can affect the resistance of a wire are length; a longer wire will make it more difficult for current to flow, as there is more material to travel through therefore the resistance increase. The cross sectional area; the larger this is, the more charge can travel at the same time through a given length, so the resistance decreases.

To calculate the resistance of a wire I will need to use the following formula:

Middle

15

0.78

1.30

1.67

20

0.62

1.34

2.16

25

0.50

1.36

2.72

30

0.42

1.38

3.29

35

0.37

1.39

3.76

40

0.33

1.40

4.24

45

0.28

1.41

5.04

50

0.24

1.42

5.92

55

0.22

1.43

6.50

60

0.22

1.43

6.50

65

0.22

1.43

6.50

70

0.19

1.44

7.58

75

0.18

1.44

8.00

80

0.16

1.44

9.00

Below is the 2nd set of results:

 Length of Resistance wire (cm) Current (Amps) Voltage (Volts) Resistance (ohms) 15 0.79 1.27 1.61 20 0.60 1.32 2.20 25 0.48 1.36 2.83 30 0.40 1.36 3.40 35 0.37 1.37 3.70 40 0.32 1.38 4.31 45 0.28 1.39 4.97 50 0.26 1.40 5.38 55 0.24 1.40 5.83 60 0.22 1.41 6.41 65 0.20 1.42 7.10 70 0.19 1.42 7.47 75 0.18 1.42 7.89 80 0.17 1.43 8.41

Below is the 3rd set of results:

 Length

Conclusion

I feel that the only way that I could have improved the practical to maybe make all the results exactly on the best line of fit would maybe be the aspect of the ruler. This is because contact with the wire placed on the ruler was only needed to record the results. This may have been where some errors or inaccurate readings were taken. So maybe measuring each piece of wire and cutting it to the required length rather than using the same piece and just changing the point of contact.

This evidence does support a firm conclusion as if someone was to repeat the same investigation I would expect the to receive the same results.

If I were to re-do the experiment, I would test the same factor again, but maybe test a larger range to see whether the pattern that I recorded in this experiment would be repeated. Or I could perhaps test a shorter length but as my preliminary results showed that the wire increased in temperature I would have to add a variable resistor. However I could change the factor I test altogether- I think I would pick to change the type of wire that the resistance wire was made of.

Katie Matthews        Physics        -  -

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 of a Wire Investigation

Thus, as the amount of sunlight, or in this case light from a bulb, falls on the plant, more energy is absorbed, so more energy is available for the chemical reactions, and so more photosynthesis takes place in a given time.

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

But all the rest stay constant and they were: > The length of the wire (by using the same length of wire throughout the experiment). > The temperature (this was achieved by not turning the circuit on unless I have to as to keep the temperature of the wire as

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

1.53 0.53 2.89 0.94 0.33 2.85 2.87 ANALYSIS OF RESULTS AND CONCLUSION As can be seen from the table of results concerning how the length of a wire affects its resistance, as the length of the wires increase so do their resistances.

2. ## In this investigation I will be looking at how certain factors affect the resistance ...

Resistance is measured in Ohms. The resistance of materials for which Ohm's law is valid does not change over enormous ranges of voltage and current. Ohm's law can be interpreted into a mathematical equation. This can then be used to calculate the Voltage, Current or resistance when possessing 2 out of the three variables.

1. ## An investigation into the factors that affect resistance.

An ammeter has to be put directly in the path of the current, so that they can check everything that goes through the circuit. The ammeter is there to show as how much current has gone through the circuit. WHAT IS LAW?

2. ## Resistance in a Wire Investigation

The factors that I will keep the same are: i) the temperature (although the resistance in constantan is quite constant over a wide range of temperatures.) ii) the thickness of the wire iii) the type of wire When measuring the resistance in the thickness of the wire, the independent variable is the thickness and the dependant variable is the resistance.

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