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

To investigate the behaviour ofan elastic material when a tensile force is applied.

Extracts from this document...

Introduction

Sian Jones 11BGC

Aim: To investigate the behaviour of an elastic material when a tensile force is applied.

What I know: In the 1660s Robert Hooke investigated how springs and wires stretched when loads were applied. He found out that for many materials, the extension and load were in proportion provided the elastic limit was not exceeded.

image00.png

 Materials can be compressed as well as stretched. If a material is stretched but springs back to its original shape they are known as elastic. However they stop being elastic if bent or stretched too far. They either break or become permanently deformed.

 The springs represent the bonds caused by the forces of attraction and repulsion between the atoms, due to the electric charges of their nuclei and electrons.

 The attractive forces between the molecules in a solid provide its characteristic elastic or stretchy properties. When we stretch a solid, we are slightly increasing the spacing of it molecules.

 The tension we can feel in a stretched spring is due to all the forces of attraction between the molecule in the spring.

Possible variables: I could change

  • The mass of load
  • Material of spring
  • Length of spring

Variables I will study: I will study the mass of load.

How I will make my test fair and why:

...read more.

Middle

I measured the length of the spring to the nearest millimetre using a ruler.I marked a line on the ruler for the length of the spring with ought any mass on it.I added a 100g weight onto the spring. I calculated the extension of the spring by subtracting the initial length reading for the unloaded spring form the loaded spring.I then calculated the stretching force which was the mass X N/Kg. The 10N/Kg being the pull of gravity.I then calculated the constant which was done using the formula;

Stretching force / extension

  1. I then took the weight off the spring and measured it again using a ruler to see if there was any deformation to the spring.
  2. I then repeated the method until the spring was deformed and would not return to its original state.  

Results table:  

Massimage01.png

(g)

100 g

200 g

300 g

400 g

500 g

600 g

700 g

800 g

900 g

1000 g

1100 g

1200 g

1300 g

Extension

(mm)

37 mm

77 mm

116 mm

170 mm

224 mm

268 mm

285 mm

335 mm

382 mm

408 mm

489 mm

511 mm

591 mm

Stretching force

...read more.

Conclusion

 However the masse that were added on each time (+ 100g) were very reliable as I used a correct weights.

 The spring I used was also kept separately from the other springs. This is because using a new spring would effect the results, as the one we started to use would begin to deform.

 I think that my method was suitable, because I set up the apparatus and collected all the things I needed before starting the investigation.

 I also measured the extension and the deformation in a correct order that suited my experiments.

 My measurements were as accurate and reliable as I could make them using the apparatus I had. I made sure that every individual weight was done correctly.

 To improve my investigation for next time, in order to get more evidence for my conclusion I will do a number of things.

  1. Make sure that a splint is used for all the individual mass
  2. Measure the extension and deformation more accurately using a more reliably measuring device.
  3. I will repeat the investigation in order to collect more results.
  4. Investigate other elastic and plastic materials to see if there is any relationship between their extension and stretching force. I will then be able to comment on the elastic limit of different materials.
  5. I could use different length springs.
  6. Use smaller weights so I can get a more accurate reading of its elastic limit.

...read more.

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

  1. Determine the value of 'g', where 'g' is the acceleration due to gravity.

    Random error, is the error made during measurements, e.g. experimenter doesn't take the readings properly. Extension of the spring could not be measured by a meter ruler hence equipment not sensitive enough. The experimenter could not stop the stopwatch at the exact time, hence the human error. If random error is very small we say the measurements are precise.

  2. The aim of this investigation is to examine the effect on the spring constant ...

    constant's produced tie in extremely well with the predictions made earlier in the investigation plan. This is especially evident if the spring constants are approximated, as doing this cuts out some of the experimental error (due mainly to the difficulty of reading results as will be discussed later)

  1. Investigation of the relationship between extension of a spiral spring material per unit of ...

    So the elastic limit will have to be found out so its not passed, it does pass its elastic limit we start to get anomalous results. The elastic limit in this experiment is 1000g. So the number of weights used have to be less than 1000g or 1kg which = 1N.

  2. Investigating Hooke's Law

    is using the formula below; Extension = New length - Original length The way that I will find out an average from my results is to use the formula below; Average = Results � Total number of entries Independent variable: Weight Applied Dependant variable: Extension Step by Step Method 1- Gather equipment needed and put on safety goggles.

  1. An Investigation into Hooke's Law - The aim of this experiment is to find ...

    Apparatus: These are the equipment pieces id need to use: * 30cm Ruler * Spring with hooks at each end. * Retort stand and clamp * Varied Selection of weights * Weight holder with hook at the end. Method: * Collect and set up apparatus as shown in diagram.

  2. Investigation into Hookes Law - investigate the effect of mass on the extension of ...

    Conclusion: This experiment has showed that I was only half right in my prediction, I did say that the extension will increase when the mass has increased, that was the correct part. The bit where I was wrong was when I said the extension would double when the mass doubles.

  1. Investigating Hooke's Law into thin wires.

    attach the metre rule using a clamp, ensuring that it is perfectly vertical. ??Cut piece of fishing wire about 60-75 cm in length. ??Attach the wire to the clamp, leaving a loop at the bottom in order to hang the force.

  2. An investigation into the stretching of materials

    If the force is too strong, my research below tells me that Hooke's law no longer applies. The elastic limit is the maximum amount of stress a material can stand before it becomes permanently deformed. For example, when small weights are suspended from a spring, doubling the weight doubles the extension (Hooke's law)

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