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

For this investigation I will be testing various materials to determine how much force is required for them to snap.

Extracts from this document...


A2 Physics investigation

For this investigation I will be testing various materials to determine how much force is required for them to snap. Figure 1 below shows the forces that will be acting upon the test material.


The set-up above will increase the force applied to the test material until a crack, started in the surface in tension, propagates to cause the material to break. To experimentally determine the level of stress that is required to break an object, I need to be-able to exert a force onto an object and be able to quantitatively measure and record that force. This, I found, is not as simple as it sounds due not only to the limited equipment available to me, but also to what I could use practically and safely. I came up with many methods of measuring the force exerted as well as many ways of creating that force. A summary of the major methods and their associated problems is included below.

Method 1: Creating force using my own strength.

This has several obvious advantages including ease of use. My own strength requires no preparation to use, is easy to store when I’m not using it and can create a very broad range of force i.e. up to 800N. Unfortunately for all the benefits, there are several disadvantages that make this method untenable. The greatest concern is safety, namely my own safety.

...read more.


Method 6: Creating the force using weights.

This method of producing force has the added benefit of measuring the force as it is produced. The force produced is quantitative, steady and the maximum level reached is easily found. There are disadvantages however; the maximum force that can be produced is dependant on the maximum strength of the string that attaches the masses to the test medium. The larger the area of contact, the less pressure is produced. This means that for the test to be fair, the string used has to be the same in each instance. This method is the one that I finally decided to use.

My choice of method means that a small alteration is required to my original force diagram; see figure 2.


Fair Test

In order to perform this experiment fairly I will need a means of supporting the material and ensuring the struts stay in the correct place because the force I exert will be laterally transferred to them. I considered several ways of supporting the material and how to prevent the supports shifting during testing. Figure 3 shows the forces involved.

Vertical force applied to material, causing it to flex and become compressed and under tension.


The flex of the material means that the edges of the material are closer the centre of the material and that the material is therefore shorter horizontally despite being slightly longer in length.

...read more.


The first thing that I thought would be a safety concern in the experiment was the force involved in breaking the materials. Creating large forces would mean large amounts of mass being used and this is a hazard. To minimise any risk involved; I selected materials that would not require huge forces to break and I used only small samples of them so as to further reduce the force required e.g. the wood samples I used were cut to a thickness of 2mm.

Another concern was that of what the material would do when the stress point was reached. Some of the materials I used could shatter or splinter e.g. plastic and wood. To cut the risk of personal injury to myself and those around I erected Perspex safety screens, wore protective goggles and performed the experiment in a closed classroom. I also used shatterproof plastic in tests instead to normal plastic as I considered this too dangerous.

Due to the method used in generating the force i.e. using suspended masses, I had to consider where the masses were going to land once the material gave way. I placed a carpet tile where the masses were going to fall so as to prevent damage to the floor and furthermore I suspended the masses as close to the floor as possible so as to reduce the velocity at which the impacted the floor.

With the preparation of the experiment sorted and a few preliminary test runs completed, I decided to start collating results from the various materials I had collected.

...read more.

This student written piece of work is one of many that can be found in our GCSE Forces and Motion 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 Forces and Motion essays

  1. Squash Ball and Temperature Investigation

    was made to make the testing of the ball fair by testing the same ball made of the same material (using the same ball ensured that the amount of air in it was the same so air pressure was not affected, it's diameter would be kept the same and also

  2. Investigate the various ways in which physics is involved to create exhilarating rides in ...

    If an object has a high velocity it means the object is travelling at high speed between two given positions. After I have calculated my estimate of the height of the tower, I will be able to begin to calculate the average velocities throughout the stated stages of the ride.

  1. Strength of a string practical investigation

    Measurements of wire length in meters and wire diameter in millimetres (later converted to meters by dividing by one thousand). 3. Record the measurements of string length and diameter. Then work out cross-sectional area of the wire by halving diameter to get the radius of each string and then put in to the formula ?

  2. Acceleration, Force and Mass

    Preliminary Experiment and Method: Before any experiment is taken out, there should always be an experimental trial to determine factors such as ranges and to make alterations to the overall set-up to gather the most accurate data that is possible.

  1. Investigate how the weight of an object affects the force required to overcome friction.

    and the mass of the object. I predict that the heavier the object is when on a particular surface the more force will be required to overcome friction. I also predict that the static and dynamic friction will be directly proportional to the weight of the object pressing down onto the surface.

  2. Designing a children's slide, making it exciting for the children whilst exercising safety.

    I have decided to design a slide for children of aged 5 years old to 8 years old. After going to research in local playgrounds I have come to decide that the length of my slide will be 3.5 metres, which appear to be the average length for slides.

  1. Prove that "Frictional Forces are Surface dependant".

    There is also rolling friction, which is the resistance produced when a rolling body moves over a surface. E.g.: the friction between a car tyre and the street is rolling friction. Fluid Friction/ Viscosity are the third type of friction.

  2. "Oh My Elbow - Investigation Into Force Applied To Elbow Joint".

    different arm lengths) * The angle of the ruler to the vertical The variable that I am going to be changing throughout my investigation is the angle of the ruler to the vertical, and if time constraints permit I will also be investigation the effect that changing the weight of the fixed masses has on my results.

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