• Join over 1.2 million students every month
• Accelerate your learning by 29%
• Unlimited access from just £6.99 per month
Page
1. 1
1
2. 2
2
3. 3
3
4. 4
4
5. 5
5
6. 6
6
7. 7
7
8. 8
8
9. 9
9
10. 10
10
11. 11
11
12. 12
12
13. 13
13
14. 14
14
15. 15
15
16. 16
16
17. 17
17
18. 18
18
19. 19
19
20. 20
20
21. 21
21

# Strength of a string practical investigation

Extracts from this document...

Introduction

Strength of a string practical investigation

This coursework assignment requires me to collect, analyse and evaluate data about the strength of manila string. It entails investigating the young’s modulus of the string and other methods to complete my investigation.

Aims:

1. To collect data on the strength of manila string by conducting a practical experiment.
2. To calculate figures of young’s modulus for the manila string and draw stress and strain graphs from the data calculations
3. To discuss the physics involved

Plan:

In this investigation I will collect results on the extension of manila string when certain forces are applied to it, for which I will analyse and calculate the young’s modulus. The results I will collect are for twisted manila string, I will collect three sets of results for one strand, two strands and three strands of manila string. The data will be averaged to give more accurate results and these averaged results will be used to create graphs, calculate young’s modulus of string and I will analyse the graphs to complete my investigation.

I will be drawing force and extension graphs from the averaged data. I will also calculate the stress and strain values and plot this on a graph. I will analyse both graphs and if any patterns exist I will analyse them to make judgements and conclusions.

I will use Microsoft excel spreadsheet program to make the data tables, using the data I have collected. Formulas will be used to calculate average extension, stress, strain and young’s modulus from the data collected. All the results and numerical values will be set to two significant figures of accuracy.

I have included a diagram of the set-up (figure 1) below which was used to obtain the results.

Figure 1 (Source: AS Physics CD-ROM)

Middle

14.7

2

19.6

2.5

24.5

3

29.4

3.5

34.3

4

39.2

4.5

44.1

5

49

5.5

53.9

6

58.8

6.5

63.7

7

68.6

7.5

73.5

8

78.4

8.5

83.3

9

88.2

9.5

93.1

10

98

Table 3

 Single strand Extension (m) Load (kg) Test 1 Test 2 Test 3 Average extension (m) Force (F=ma) Stress (F/A) Strain (E/L) 0.5 0.001 0 0.001 6.67E-04 4.9 1.73E+07 1.03E-03 1 0.002 0.001 0.002 1.67E-03 9.8 3.46E+07 2.56E-03 1.5 0.003 0.002 0.003 2.67E-03 14.7 5.19E+07 4.10E-03 2 BREAK 0.003 BREAK 1.00E-03 19.6 6.93E+07 1.54E-03 2.5 BREAK

Table 4

 Double strand Extension Load (kg) Test 1 Test 2 Test 3 Average extension (m) Force (F=ma) Stress (F/A) Strain (E/L) 0.5 0 0 0 0.00E+00 4.9 4.34E+06 0.00E+00 1 0.001 0.001 0.001 1.00E-03 9.8 8.67E+06 1.54E-03 1.5 0.002 0.001 0.001 1.33E-03 14.7 1.30E+07 2.05E-03 2 0.002 0.002 0.002 2.00E-03 19.6 1.73E+07 3.08E-03 2.5 0.003 0.002 0.002 2.33E-03 24.5 2.17E+07 3.59E-03 3 0.003 0.002 0.003 2.67E-03 29.4 2.60E+07 4.10E-03 3.5 0.003 0.003 0.003 3.00E-03 34.3 3.04E+07 4.62E-03 4 0.004 0.004 0.003 3.67E-03 39.2 3.47E+07 5.64E-03 4.5 0.004 0.004 0.004 4.00E-03 44.1 3.90E+07 6.15E-03 5 BREAK BREAK BREAK

Table 5

 Triple strand Extension (m) Load (kg) Test 1 Test 2 Test 3 Average extension (m) Force (F=ma) Stress (F/A) Strain (E/L) 0.5 0.001 0.001 0.001 1.00E-03 4.9 1.93E+06 1.54E-03 1 0.001 0.001 0.001 1.00E-03 9.8 3.86E+06 1.54E-03 1.5 0.001 0.001 0.001 1.00E-03 14.7 5.

Conclusion

Resources and bibliography

The resources I used were:

• Digital camera: To create evidence that I carried out my experiment and to better explain how I conducted my experiment.
• Computer: this was used to put my results on and formulas were created to create averages, stress, strains and Young’s modulus calculations.
• Computer graphs: I used excel to produce graphs with error markings, as the error markings were shown clearly when using excel when compared to hand drawn error bars, and thus resulted in better analysis.
• AS physics text book: very useful, chapter 4-5 are very useful and contained lots of information on the physics theory of my investigation (9/10)
• AS-physics CD-ROM: provided guides on how to set out coursework and information on the experiment hat this coursework was based on. (8/10)
• AS Physics teacher: Miss Bottomly: Very helpful. Introduced coursework, hence this would not have been possible without teachers help. (10/10)
• http://www.instron.com/applications/test_types/tension/index.asp: very good website, good introduction to what tensile testing is. (8/10)
• http://www.tensiletest.com/: poor website for information, do not reply to emails and have little educational information about tensile testing, only selling services (1/10)
• Collins instant revision, AS physics. Published 2002. Martin Gregory. Good diagrams and graphs, basic relevant information. (4/10)

Log Book

 Date Activity 16/6/04 Received briefing about the coursework and chose title. Began researching. 21/6/04 Researched about tensile testing, looked in revision books and textbooks. 23/6/04 Conducted preliminary experiment. Also began write up. 24/6/04 Continued write up, up to end of preliminary results. Made changes to methods for real experiment. 25/6/04 – 29/6/04 Continued with write up 30/6/04 Took main results. 1/7/04 Analysed main results, made observations and input data onto a spreadsheet program. 3/7/04 Graphed results and started analysis and conclusion 4/7/04 – 8/7/04 Completed analysis and conclusion. Also finished evaluation. Completed bibliography and summary. Read through coursework. 10/7/04 Rechecked and completed coursework.

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

# Related GCSE Forces and Motion essays

1. ## Factors Influencing Resistance of a Wire

3 star(s)

Prediction I predict that the longer the wire is, the more resistance there is. I predict this as the longer the wire is, the longer the crystal lattice is, and therefore the more atoms there are. This is shown in the diagram below.

2. ## Mechanics 2 Coursework - 'woosh' down the slide

For the first and second graphs, ?=30�and ?=35�, most part of the 'actual lines' lie within the error bounds. However, the last graph ?=40�, the whole 'actual line' is not in the error bounds. I guess the reason for this is the contact surface between the block and the wood ramp.

1. ## My objective in this experiment is to find out how a spring varies in ...

For example, the Young's Modulus of Mild Steel = 2 x 1011 N m-2 Copper = 11 x 1010 N m-2 Hooke's Law and Young's Modulus apply to most elastic materials, with the exceptions. A special shape which material can be bent into to in order to optimize use of the elasticity of a material is a spring.

2. ## In this experiment I aim to find out how the force and mass affect ...

The second table shows the initial velocity, final velocity, initial time, final time and how they were used to calculate the acceleration of the trolley. Table One Experiment Number Length of Runway, L in metres Height of Slope, H in metres Angle of Runway, ? = Tan (L/H), in degrees

1. ## Energy Conversion

Energy output: m = 100 � C = 4.2 � ?T = 13 = 5460 Energy output = 5460 (J) Gas to Heat The calorific value of British gas is 39.5kJ kG-1and I have used 320g of British gas. Energy input: 320 � 39.5 = 12640 (J)

2. ## The Helicopter Investigation

These results are yet again to 2 decimal places to achieve a more precise range of results, and an average is used to calculate the average of all the three attempts. Wing span length Test 1 in (m/s) Test 2 in (m/s)

1. ## Physics P2 Topic Overview Coursework

when they crash (longer for change in momentum): * Crumple Zone - bonnets take a long time crumple * Seat Belts - stretch so there is less force acting on chest * Air bags - slow you down Roller coasters and Relativity Energy is always transferred; Food enables us to move (Chemical --> Kinetic)

2. ## Mechanical Properties of a Meter Rule

With this experiment I will be able to find many different things, like the modulus of elasticity for different materials, bending stress, the energy stored as it deforms etc. . The second experiment I will do is the compound pendulum, with this I will be able to work out the

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