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

Does the length of a conduction putty affect its resistance?

Extracts from this document...

Introduction

Physics coursework - Does the length of a conduction putty affect its resistance?

Hypothesis:

                 I predict that as the length of the conducting putty increases, its resistance will increase. This is because as the length of the conducting putty increases, the current will have to pass through more molecules of the element(s) that the conducting putty is made of. This will make it harder for the current to pass through the conducting putty and so the electrons that compose the current will collide with more of the elements that make up the conducting putty. This causes friction between the electrons and the molecules and so heat is dissipated, which makes the circuit less efficient. This means that the putty is acting restricting the flow of electrons around the circuit more efficiently as its length increases, hence it is a better resistor.

        In order to calculate the resistance of the wire, I plan to use Ohm's Law, the formula for this law being:

V=IR

When rearranged, it can be used to calculate the resistance of a substance, which I will need in my pre-testing and main experiment, to see if the resistance of the putty chances as its length decreases:

R= V/I

...read more.

Middle

5.37

0.21

25.57

4

3.49

0.14

24.93

12 

8

7.33

0.35

20.94

22.13 

6

5.34

0.24

22.25

4

3.48

0.15

23.20

8

7.04

0.52

13.54

13.86 

6

5.18

0.37

14.00

4

3.37

0.24

14.04

8

6.56

1.24

5.29

5.58 

6

4.84

0.9

5.38

4

3.03

0.5

6.06

These results prove that the putty that I am investigating is an Ohmic conductor, as even when the potential difference changes, the resistance of the putty remains constant for the same length.

Now that I have proved that the putty does conduct electricity in a constant manner, I can start the main experiment.

Apparatus:

  • 1 power pack
  • 2 thin copper sheets -these are required in order to improve the efficiency of the volume of current that flows through the putty.
  • Emery paper - this will be used to file the copper sheets and so improve their conductivity.
  • A mass of putty
  • 1 small knife
...read more.

Conclusion

The other safety precaution that I will take during this experiment is to constantly make sure that there is no water near any of the apparatus that I am using in the experiment, nor nears the mains supply. I will also make sure that there is no water on my hands for the duration of the experiment, as water conducts electricity and so if I had water on my hands I could be electrocuted.

Finally, before I eat anything, I will make sure that my hands are thoroughly washed with soap and water, in order to get rid of any traces of putty that may have come into contact with my hands during the experiment, as they could be toxic. I will follow this safety precaution even though I am wearing gloves, as small tears could occur in the gloves during the course of the experiment.

Results:

On the following pages are the results that I obtained from my experiment. The 4th page of tables shows the average results that I obtained and hence used to plot the graphs that I have drawn in Analysis.

...read more.

This student written piece of work is one of many that can be found in our AS and A Level Electrical & Thermal Physics 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 AS and A Level Electrical & Thermal Physics essays

  1. Characteristics of Ohmic and non-Ohmic Conductors.

    Resistance is constant throughout, and thus it proves that the metal wires are ohmic conductors. Non-Ohmic Conductors Filament Lamp From the graph and table for the filament lamp, I have noted, that as voltage increases, current increases too, but at a smaller rate.

  2. Practical Assessment for Physics: Investigating the Resistance of Conducting Putty.

    Finally to find out the resistants for each length of putty I divided the voltage average to the current average for each length of putty giving me the resistants of each length of putty. Results: VOLTAGE READING Reading No. 1cm 3cm 5cm 7cm 9cm 1 4.23 4.78 4.99 5.29 5.62

  1. The Resolving Power Of The Eye

    The calculated resolving power is less than the theoretical value as expected and by assuming the triangles inside and out of the eye are the same an accurate answer of separation can be found so the refraction is little as light passes through the lens.

  2. Investigating the effect of 'length' on the resistance of a wire

    Length (m) The formula which I will mainly be using in the investigation is the resistance equation: Voltage (V) ____________ = Resistance (R) or V/I = R Current (I) Preliminary Test: I carried out a preliminary test (or a trial run)

  1. Characteristics of Ohmic and Non Ohmic Conductors.

    The others that do not obey Ohm's Law are called Non Ohmic Conductors. Conductors such as pure metals are ohmic conductors. In this case the ohmic conductors have to be kept under constant pressure and constant temperature for them to behave as ohmic conductors.

  2. Investigating how temperature affects the resistance in a wire

    So to combat this problem I must change the method so as to make the results more accurate and reliable; the factors that contributed to the inaccuracy of the results of the preliminary experiment was; * The large amount of wire used in the experiment * The large amount of

  1. To investigate the resistance of a conducting material as its length changes.

    due to an increase of kinetic energy in the structure, causing vibrations and leading to more collisions - more electrons are released from the structure of the graphite as free electrons which themselves can increase the flow of current. This means that either � the rate at which resistance increases

  2. Energy Efficiency Experiments

    Experiment Mass(g) 0.24 Temp of water (°c) 21 Voltage(V) 8.6 Current(A) 2.73 After 4 minutes Temp of water (°c) 27 Final mass(g) 0.17 Temp difference (°c) 6 Mass difference(g) 0.07 ⯠http://glossary.periodni.com/images/calorimeter.jpg Distinction The most efficient out of all the experiments was experiment 4 because a small amount of electrical energy produced kinetic energy + heat energy which caused gravitational potential energy + more heat energy.

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