DFACULTY of COMPUTING, ENGINEERING & SCIENCE Assessment Cover Sheet and Feedback Form 2016/17 Module Code: G1S22 Module Title: Engineering Mechanics Module Lecturer: Constant Dewy Assessment Title and Tasks: Condition of Equilibrium – ladders Assessment No. 1 of 3 Statics Lab No. of pages submitted in total including this page: Completed by student Word Count of submission (if applicable):Completed by student Date Set: WC 28/11/2016 Submission Date: 13/01/2017 @ 13:00 Return Date: 03/02/2017 @ 13:00 Part A: Record of Submission (to be completed by Student) Extenuating Circumstances If there are any exceptional circumstances that may have affected your ability to undertake or submit this assignment, make sure you contact the Advice Centre on your campus prior to your submission deadline. Fit to sit policy: The University operates a fit to sit policy whereby you, in submitting or presenting yourself for an assessment, are declaring that you are fit to sit the assessment. You cannot subsequently claim that your performance in this assessment was affected by extenuating factors. Plagiarism and Unfair Practice Declaration: By submitting this assessment, you declare that it is your own work and that the sources of information and material you have used (including the internet) have been fully identified and properly acknowledged as required 1 . Additionally, the work presented has not been submitted for any other assessment. You also understand that the Faculty reserves the right to investigate allegations of plagiarism or unfair practice which, if proven, could result in a fail in this assessment and may affect your progress. Intellectual Property and Retention of Student Work: You understand that the University will retain a copy of any assessments submitted electronically for evidence and quality assurance purposes; requests for the removal of assessments will only be considered if the work contains information that is either politically and/or commercially sensitive (as determined by the University) and where requests are made by the relevant module leader or dissertation supervisor. Details of Submission: Note that all work handed in after the submission date and within 5 working days will be capped at 40% 2 . No marks will be awarded if the assessment is submitted after the late submission date unless extenuating circumstances are applied for and accepted (Advice Centre to be consulted). You are required to acknowledge that you Student Number(s): 1 University Academic Misconduct Regulations 2 Information on exclusions to this rule is available from the Advice Centre at each Campus have read the above statements by writing your student number(s) in the box: IT IS YOUR RESPONSIBILITY TO KEEP RECORDS OF ALL WORK SUBMITTED Plagiarism Whether the assignment is individual or group work, you must NOT engage in plagiarism in writing it. Plagiarismis deliberately or carelessly passing off another's work as your own and includes copying the words, ideas or research results of another without acknowledging the author as a source. It is plagiarism, therefore, to copy the work of another student or of a member of staff, or a published article or book without crediting the author. Acknowledging (crediting) a source requires more than an entry in your bibliography at the end of your work – it requires proper referencing or annotation (use of footnote or endnote) giving the author, title of the work (book or article), title of journal, date and page numbers(s) at which the reader can find what you are referring to. If you quote someone verbatim, quotation marks are required and the text should normally be italicised. Detailed Requirements Your task is to conduct a laboratory test and produce a word-processed lab report of 2000 words (+/- 10%). You will be penalised by 10% for missing the word count. Your submission will be electronic via Turnitin look in the assessment tab in BB, DO NOT INCLUDE THE LAB BRIEF / COVER SHEETas it skews the plagiarism report, just submit the report. A typical lab report should include: • Title page • Abstract/Summary • Table of Contents • List of Figures/Tables (if applicable) • Introduction • Background Theory • Experimental Procedure/Methodology • Results and Analysis (tables, graphs, figures, calculations) • Discussion of Results • Conclusions and Recommendations • References • Appendices (if applicable) When preparing your analysis, you are free to make assumptions. However all assumptions must be clearly stated and justified in your report. You are expected to do additional research and reading as part of this assignment. All source material must be referenced according to the Harvard Referencing system. Part B: Marking and Assessment Assessment Task: Condition of Equilibrium – Ladders Figure 1 For a ladder to have equilibrium when it rests against a wall under its own weight and also with an additional weight, the forces around the ladder must balance, or the ladder will fall down. From the laws of equilibrium, the sum, of the vertical forces must equal zero and the sum of the horizontal forces must equal zero. In a practical application (as shown in the experiment), the horizontal forces on the ladder are the most important. The force at the top of the ladder against the vertical wall determines whether the wall can withstand the ladder leaning against it. The force at the bottom of the ladder determines whether the ladder will slip. The experiment and theory should prove that the vertical reaction force stays reasonably constant through the tests. Measuring Ladder Angles During the ladder experiments you need to Use different ladder angles. To find the angle, find the vertical distance (δy) and the horizontal distance (δx) from the top and bottom of the ladder. Use trigonometry to find the angle. To measure the forces correctly, you must adjust the loads and the position of the spring balance so the ends of the ladder 'float' inside the 'U' shaped supports (see Figure 2 ). Figure 2 a Figure 2 b The supports have the 'U' shape to help to stop the ladder slipping away as you make adjustments. Each rung has small clips to help make sure you put the hooks at the middle of the rungs ( see Figure 3 . This helps to stop the ladder 'twisting' and upsetting ) your results. Figure 3 Aims  To show how to predict the horizontal forces on a ladder of fixed mass at different angles.  To show how the horizontal forces on a ladder change for different ladder angles. Procedure • Complete a results table, similar to the table below. • Weight the ladder. • Fit the parts to the Work Panel as shown in Figure 1. The exact positions are not critical as you will make slight changes as you do the experiment. • Temporarily unhook the spring balance and zero its indicator by holding the top hook and adjusting the control until the pointers line up at zero. • Refit the balance to the Work Panel. This balance will measure the horizontal force at the bottom of the ladder. • Adjust the magnetic mounts (with the 'U' shape holder), so the ladder is at 15° to the vertical • Add a load of 300g to the middle rung of the ladder, using a short cord. This simulates a heavy ladder or a load at the middle of the ladder to give good results with this equipment. Smaller loads will give lower force readings and less accurate results. • Carefully add masses to the weight hanger that pulls the ladder upwards from the bottom. This is equal to the vertical force. Stop adding weights when the ladder just starts to 'float' in its bottom mount. The masses on this hanger should equal the total load (the weight of the ladder and the load at the middle rung). This proves, the first part of the theory (vertical reaction = load of ladder). • Carefully add masses to the hanger that pulls the top of the ladder horizontally until the ladder starts to 'float' in this mount. This force is equal to the horizontal force. • Recheck the ladder angle and record. • Repeat the experiment for other ladder angles as shown in the results table. RESULTS TABLE Angle (°) Spring balance reading (N) Mass used to float bottom of ladder (g) Mass used to float top of ladder (g) 3.4 N 510 g 290 g 3.8 N 510 g 350 g 5.4 N 510 g 560 g Results Analysis - Tips • You must consider the ladder mass in this experiment. • Find the value of the ladder angles, and calculate the experimental values. • Your results should show that the vertical reaction stays reasonably constant. • Create a chart of horizontal reaction force against ladder angle. Draw a 'best fit' line through your results and extend the line downwards towards the origin of the chart. • What does the chart show, and how does this affect how a person would use a ladder? What ladder angles do you suggest would be safest for a person to use a ladder? • Did the analytical summation of forces show the system to be in equilibrium? If not, suggest possible sources of inaccuracy (ideally in terms of percentage of error/difference). • Have there been any losses due to friction in the above experiment? If so, explain this in detail. • Detail any error, in terms magnitude, and highlight where this occurs. Learning Outcomes to be assessed (as specified in the validated module descriptor https://icis.southwales.ac.uk/): LO1. Demonstrate an understanding and the ability to solve problems in simple static and dynamic or structural systems using experimental analysis Grading Criteria: This lab is worth 30% of your overall marks, it is not bonded, you need to pass this activity in order to pass the module. Outline Marking Scheme Marks Available Presentation, structure and referencing 10 Knowledge of theory and clarity of aims and objectives 15 Results and calculations 40 Discussion 20 Conclusions 10 Recommendations 5 Total 100 Feedback/feed-forward (linked to assessment criteria): • Areas where you have done well: • Feedback from this assessment to help you to improve future assessments: • Other comments Mark: Marker's Signature: Date: Work on this module has been marked, double marked/moderated in line with USW procedures. Provisional mark only: subject to change and/or confirmation by the Assessment Board Part C: Reflections on Assessment(to be completed by student – optional) Use of previous feedback: In this assessment, I have taken/took note of the following points in feedback on previous work: Please indicate which of the following you feel/felt applies/applied to your submitted work • A reasonable attempt. I could have developed some of the sections further. • A good attempt, displaying my understanding and learning, with analysis in some parts. • A very good attempt. The work demonstrates my clear understanding of the learning supported by relevant literature and scholarly work with good analysis and evaluation. • An excellent attempt, with clear application