• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

The aim of this investigation is how the resistance of a nichrome wire changes as the length of the wire changes.

Extracts from this document...

Introduction

Sohail Ali 10.403/04/01

Science Coursework

An Investigation on Resistance of a Wire

Aim

The aim of this investigation is how the resistance of a nichrome wire changes as the length of the wire changes.

Background Knowledge

Ohms law states a relationship between voltage (V), current (I) and resistance (R). If the voltage is increased then more current will flow, but if the resistance is increased this will decrease the flow of the current.

        This is because the resistance is conflicting with the flow: it makes it difficult for the electrons to pass around the circuit therefore slowing the flow down.

        The voltage is in fact a driving force, pushing the current around the circuit. The voltage supplies the push for the current to pass around the circuit and pass the resistance in the circuit; the amount of resistance and voltage decides how the amount of current passing through the circuit. If two of the three principles are available, then the following formula may be used to calculate the third.

V = IR

Resistance is proportional to the length of wire, this according to various textbooks. Therefore a prediction should consist of; the greater the length of wire the higher the resistance.

...read more.

Middle

4) Keep everything constant except the length of wire.

5) Switch on the circuit for only a short time (Otherwise the                     wire would have got hot and resistance would increase, therefore making the test unfair)

6)  Read the current using the ammeter.

7) Read the voltage using the voltmeter.

8) Record results in a table.

9) Worked out the resistance using Ohms law:

Resistance (Ω) = voltage across wire (V), current through the wire (I).

10)        Repeat this method, now simply

...read more.

Conclusion

Ω). This also backed up my prediction.

Evaluation

I think my results were as accurate as they could be, as the readings were rounded up to 2 dp. So the results weren’t 100% accurate.

I think that the experiment was generally a fair test but in some ways it wasn’t for example the length of the wire was not always exact maybe a couple of mm difference. Temperature is one of the key factors of resistance; for example in our experiment the temperature of the wire was high therefore the resistance become greater. It affects the resistance by making it higher as the electrons move faster at higher temperatures. I don’t think this experiment could be made any fairer as we did everything that we could to make this a fair test because the only way to make the experiment fairer was to be more accurate with the measuring of the wire. There are many different ways of extending our work to get more answers on the different affects on resistance. One way is by seeing how the thickness of a wire would affect the resistance. Or by experimenting with different materials and how they affect resistance.

...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)

    Average Current (mA) Current (decreasing in voltage) Current (increasing voltage) Voltage (V) Sly. No 6.13 24.45 24.90 24.00 0.15 1 6.13 32.60 33.00 32.20 0.20 2 5.83 42.85 43.00 42.70 0.25 3 5.85 51.25 50.90 51.60 0.30 4 5.85 59.85 60.10 59.60 0.35 5 4.80 83.25 96.90 69.60 0.40 6 5.68 79.25 78.90

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

    1.433 average V for 40cm length and 1.791?, we also see that the average voltage has also doubled as the length has doubled. This proves my point about voltage and resistance doubling as length doubles. Collision theory; The reason why if we double the length we get a doubled resistance

  1. Resistance of a Wire Investigation

    The CO2 comes in through the stomata pores on the surface of the leaf and only 0.03 % of the air around is CO2 so it's pretty scarce. Temperature has to be kept at a certain level because if it gets too hot, about 45`C then the enzymes in the chlorophyll will be killed and photosynthesis will stop altogether.

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

    Current (A) Resistance V/I (?) 0.115 0.043 2.674 0.136 0.051 2.667 0.179 0.067 2.671 0.200 0.075 2.667 0.224 0.084 2.667 0.251 0.094 2.670 0.278 0.104 2.673 0.309 0.116 2.664 0.344 0.129 2.667 0.405 0.152 2.664 Total 2.668 E34 wire with the length at 30cm Voltage (V)

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

    Each time we placed a new length of wire we timed it to make sure that the current was only flowing for 30 seconds. Once we did this we wrote down the measurement that was on the ammeter and the voltmeter and then we repeated the procedure for the other five lengths of wire.

  2. Resistance in a Wire Investigation

    As the resistance of a material increases so to must the force required to drive the same amount of current. In fact resistance, in ohms(R) is equal to the electromotive force or potential difference, in volts (V) divided by the current, in amperes (I)

  1. The aim of this experiment is to investigate how a change in the length ...

    The results were extremely accurate, and I repeated the experiment for increased reliability. Also, for the main investigation I have decided to use 2V as the input voltage. Some things I can improve on in the main investigation, is to get a more accurate rheostat, so as to be even more precise with the voltages.

  2. The aim of this investigation is to discover how the length of a wire ...

    The number of electrons depends on the amount of electrons in the outer shell of the atoms. If the material has a high number of atoms, then there will be more electrons. This causes a lower resistance because of the increase in the number of electrons.

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