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

Hooke's Law / Young's Modulus - trying to find out what factors effect the stretching of a spring.

Extracts from this document...

Introduction

Hooke's Law / Young's Modulus

I am trying to find out what factors effect the stretching of a spring.

Things, which might affect this, are:
· Downward force applied to spring.
· Spring material.
· Length of spring.
· No. of coils in spring.
· Diameter of spring material.
· Cross sectional area of spring.
I have chosen to look at the effect of the weight applied, as it is a continuous variation.
I predict that the greater the weight applied to the spring, the further the spring will stretch. This is because extension is proportional to load and so if load increases so does extension and so stretching distance.

Extension = New length - Original length

To see if my prediction is correct I will experiment, and obtain results using Hookes Law. He found that extension is proportional to the downward force acting on the spring.

Hookes Law
F=ke
F = Force in Newtons
k = Spring constant
e = Extension in Meters

My method of experimentation will be to use a clamp stand and boss clamp to suspend a spring from. A second boss clamp will hold in place a metre rule starting from the bottom of the spring to measure extension in mm. I will then add weights to the spring and measure extension.
Before deciding on the range of experimentation I carried out a preliminary test to find the elastic limit of the springs we had.

...read more.

Middle

y=mx+c <THORN> e = mf <THORN> e = f
m

Hookes Law

F=ke

By comparison

K = 1 <THORN> 1 = 28.7769
m 0.03475


This shows the spring constant is 28.7769 N/m
To check that my spring constant from hooks law was correct I am going t experiment again using Simple Harmonic Motion. If both experiments are correct the spring constant from both experiments will be almost identical.
The Simple Harmonic Motion experiment requires measurements of time over an oscillation of the spring being acted on by different forces.
My method of experimentation for simple harmonic motion will be to suspend the spring as in the first experiment and place on the required weight. I will then stretch the spring a further 15mm and then release the spring and take a time measurement for an oscillation in the spring. This however will be inaccurate due to the response time of starting and stopping the timer, because of this I have decided to time 10 oscillations and then divide the result by 10 this will reduce the experimental error. Only one test is needed to find the spring constant but I will take 5 tests each with a different weight. The equation used uses a weight measurement in Kg so the 1N masses I have available will each be 0.1Kg.

Simple Harmonic Motion

T = 2p m
T = Time in seconds k
M = Mass in Kg
K = Spring constant

...read more.

Conclusion


In the Simple Harmonic Motion test the timing of the oscillations could be taken over a greater number to help reduce experimental error.
Further investigations could use Young´s Modulus This was created by Thomas Young and gives a number representing (in pounds per square inch or dynes per square centimetre) the ratio of stress to strain for a wire or bar of a given substance. According to Hooke´s law the strain is proportional to stress, and therefore the ratio of the two is a constant that is commonly used to indicate the elasticity of the substance. Young´s modulus is the elastic modulus for tension, or tensile stress, and is the force per unit cross section of the material divided by the fractional increase in length resulting from the stretching of a standard rod or wire of the material. This would be useful as after the limit of proportionality had been reached using Hooke´s law; Young´s modulus would give results until the spring became straight until eventually breaking. However the change in length at this stage is very small and special measuring equipment would be needed in order to conduct a reasonable experiment.

...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. I am investigating the relationship between extension and load, therefore testing Hooke's Law.

    Length was measured 3 times for each weight to ensure accuracy. To find out the average length for each weight I took 3 measurements of the lengths then added them together. This value was then divided by three (the number of times length was tested).

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

    Through this graph I will try to establish a line of best fit which, (experimental inaccuracies aside), should pass extremely close to all points due to the expected linear nature of the results, such a straight line will help to prove my hypothesis that simple multiplication and division by 2

  1. Finding the Spring Constant (k) and Gravity (g) using Hooke&amp;amp;#146;s Law and the Laws ...

    a line of best fit the gradient of the line will be the spring constant (k). 14. To get another estimate of the spring constant we will create a graph using: T2 = 4?2 m k If you plot T2 against m, the gradient will equal 4?2 .

  2. Making sense of data - finding a value for the young modulus of a ...

    B = width of the ruler (strip) D = thickness of the ruler (strip) g = 9.80 Nkg-1 We repeat the above experiment two more times by measuring again the deflection of the ruler with the same weights and from the same side of the ruler.

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

    Which increases the precision of the results. Whereas in systematic errors can be totally eliminated if better techniques and instruments are used. Which will increase the accuracy of the final result by a long way. Analysis conclusion Looking at the results that I have obtain you can see that there

  2. My aim for this experiment is to verify Hooke's law, which is F = ...

    Conclusion Spring I hung a spring from a retort stand and measured its length, which was 4.7cm.

  1. Investigating Hooke's Law

    plot the graph the coordinates will be all over the place, therefore I will have to increase the mass on the spring in equal increments, e.g. 50 grams the another 50 grams e.t.c. The more number of coils affects the length of a spring because.

  2. Prove if Hookes Law's theory of extension is proportional to length is true.

    350g 13.9 13.9 13.8 13.9 11.9 400g 16 16.3 16 16.1 14.1 Analysis of graph: Looking at my graph, I feel that my experiment has been successful. All the points are near to the line of best fit, and it shows that my prediction was correct, that EXTENTION IS PROPORTIONAL

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