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

How does the length of a wire affect its resistance

Extracts from this document...

Introduction

How does the length of a wire affect its resistance?

Planning

What I will do

I will use different lengths of wire to find out the resistance each of them makes when the power supply is switched on, and the try to work out a trend for it.

My prediction

My prediction is that the longer the wire is the greater the resistance will be.

Prediction using scientific knowledge

  • When the power supply is switched on a surge of electrons run through the wire.
  • I believe that the longer the wire is the longer it for the electrons to go around the circuit and re-enter the power supply.
  • Therefore making the resistance larger.

Equipment

  • A power supply set at 2 volts
  • 3 leads with crocodile clips at each end
  • an ammeter
  • 1 beaker of water
  • 3 lengths of 60cm of wire

What I will measure

...read more.

Middle

I will take the measurement 3 times for each length of wire but at separate times.

How my results will be accurate and reliable

They will be accurate and reliable because I will get the average current from each of the lengths because I am taking them 3 times.

Obtaining Results

How I will make my investigation as safe as possible

When doing my experiment I tried to make it as safe as possible.  I did this by using a beaker of water, this stopped us picking up the wire it ws hot and we might have burnt ourselves.

Analysing Results

What I have found out

I have found out that the shorter the wire was the smaller the resistance was.

What I have found out using scientific knowledge

I have

...read more.

Conclusion

  • made sure the wire was exactly the right length.
  • I could have done the test more times so it would have given me a more accurate average.

Scientific Knowledge

When looking at my results they seem to increase in resistance the lager the piece of copper wire is.  This is because as the electrons leave the power supply they travel along the wire.  When the wire is 60cm long the electrons take longer to travel through it.  This therefore increases the resistance, but as the wire gets cut shorter. The resistance decreases as there is a smaller distance for the electrons to flow throw.

Prediction agree/disagree

After comparing my results with my prediction, I have found that my prediction was correct.  This is because my prediction says that as the wire decreases in length, the resistance also decreases.  And then when you look at my results this proves this.

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