-SQA-SCOTTISH QUALIFICATIONS AUTHORITY HIGHER NATIONAL UNIT SPECIFICATION GENERAL INFORMATION -Unit Number- 2550727 -Superclass- -Title- RC MECHANICAL ENGINEERING PRINCIPLES: STATICS AND DYNAMICS ----------------------------------------- -DESCRIPTION- GENERAL COMPETENCE FOR UNIT: Applying the fundamental concepts of statics and dynamics to the solution of engineering problems. OUTCOMES 1. analyse planar equilibrium problems; 2. quantify the effect of direct and shear forces in situations of engineering significance; 3. solve kinematic problems for linear and angular motion; 4. solve rigid body problems using Newton s second law of motion. CREDIT VALUE: 1 HN Credit ACCESS STATEMENT: Access to this unit is at the discretion of the centre. However, it would be beneficial if the candidate had prior knowledge or experience of basic statics and dynamics. This may be evidenced by possession of NC module: 64006 Dynamics 64007 Strength of Materials 74012 Statics: Components and Structures 64002 Fundamentals of Technology: Mechanical or similar qualifications or experience. -----------------------------------------
For further information contact: Committee and Administration Unit, SQA, Hanover House, 24 Douglas Street, Glasgow G2 7NQ. Additional copies of this unit may be purchased from SQA (Sales and Despatch section). At the time of publication, the cost is 1.50 (minimum order 5.00). 2
HIGHER NATIONAL UNIT SPECIFICATION STATEMENT OF STANDARDS UNIT NUMBER: 2550727 UNIT TITLE: MECHANICAL ENGINEERING PRINCIPLES: STATICS AND DYNAMICS Acceptable performance in this unit will be the satisfactory achievement of the standards set out in this part of the specification. All sections of the statement of standards are mandatory and cannot be altered without reference to SQA. OUTCOME 1. ANALYSE PLANAR EQUILIBRIUM PROBLEMS PERFORMANCE CRITERIA (a) (b) (c) (d) The description of the conditions for equilibrium is clear and concise. External reactions for statically determinate planar structures are calculated correctly. Internal loads for statically determinate pin-jointed plane frames are determined correctly. Shear force and bending moment diagrams are constructed for determinate beam systems carrying concentrated and uniformly distributed loading. RANGE STATEMENT External reactions: at roller; pinned and built-in supports as appropriate. Internal loads: tensile and compressive forces in truss members; shear forces and bending moments in beams. Determinate beam systems: simply supported; cantilever. EVIDENCE REQUIREMENTS Written and graphical evidence of the candidate s ability to compute the member forces in a statically determinate plane frame, and draw the shear force and bending moment diagrams for a statically determinate beam, as specified in performance criteria (a) to (d). 3
OUTCOME 2. QUANTIFY THE EFFECT OF DIRECT AND SHEAR FORCES IN SITUATIONS OF ENGINEERING SIGNIFICANCE PERFORMANCE CRITERIA (a) (b) (c) Hooke s law is stated correctly. Direct stress and strain are determined correctly for axially loaded components to include stepped changes in cross section excluding self straining. Shear stress is determined correctly for a simple shear loading situation. RANGE STATEMENT Simple shear loading situations: joints in single shear; joints in double shear; flanged couplings; torque transmitted; blanking operations; piercing operations. EVIDENCE REQUIREMENTS Written and/or oral evidence is required to demonstrate that the candidate can describe the effect of direct and shear forces across all classes of this range, as specified in performance criteria (a) to (c). OUTCOME 3. SOLVE KINEMATIC PROBLEMS FOR LINEAR AND ANGULAR MOTION PERFORMANCE CRITERIA (a) (b) (c) (d) (e) (f) Statement of equations of rectilinear motion under constant acceleration are precise. The solution of a rectilinear motion problem demonstrates the correct application of the appropriate equations of motion. Statement of equations of angular motion under uniform angular acceleration are precise. The solution of an angular motion problem demonstrates the correct application of the appropriate equations of angular motion. The solution of linear and angular motion problems using velocity time diagrams is correct. The relations between linear and angular motion are applied correctly with regard to rotation about a fixed axis. 4
RANGE STATEMENT The range for this outcome is fully expressed in the performance criteria. EVIDENCE REQUIREMENTS Written and/or oral evidence is required to show the candidate s ability to solve kinematic problems for linear and angular motion as specified in performance criteria (a) to (e). OUTCOME 4. SOLVE RIGID BODY PROBLEMS USING NEWTON S SECOND LAW OF MOTION PERFORMANCE CRITERIA (a) (b) (c) (d) Newton s second law, in the form applicable to rigid body motion, is stated correctly. Newton s modified second law is applied correctly to linear acceleration problems on horizontal and inclined surfaces including the effect of friction. Newton s modified second law is applied correctly to problems involving angular acceleration about a fixed axis including friction effects. Newton s modified second law is applied correctly to connected systems having one angular element and one linear element. RANGE STATEMENT The range for this outcome is fully expressed in the performance criteria. EVIDENCE REQUIREMENTS Written and/or oral evidence is required to show the candidate can solve linear and angular acceleration problems in accordance with Newton s Second Law of Motion, as specified in performance criteria (a) to (c). MERIT To gain a pass in this unit, a candidate must meet the standards set out in the outcomes, performance criteria, range statements and evidence requirements. To achieve a merit, the candidate must demonstrate a superior level of performance. Evidence of this may by supported by considering the following attributes: Understanding Attitude 5
Knowledge Initiative Innovative ability Enthusiasm, conscientiousness and application Timeous and neat presentation of achievements. ----------------------------------------- ASSESSMENT In order to achieve this unit, candidates are required to present sufficient evidence that they have met all the performance criteria for each outcome within the range specified. Details of these requirements are given for each outcome. The assessment instruments used should follow the general guidance offered by the SQA assessment model and an integrative approach to assessment is encouraged. (See references at the end of support notes). Accurate records should be made of the assessment instruments used showing how evidence is generated for each outcome and giving marking schemes and/or checklists, etc. Records of candidates achievements should be kept. These records will be available for external verification. SPECIAL NEEDS Proposals to modify outcomes, range statements or agreed assessment arrangements should be discussed in the first place with the external verifier. Copyright SQA 1997 Please note that this publication may be reproduced in whole or in part for educational purposes provided that: (i) (ii) no profit is derived from the reproduction; if reproduced in part, the source is acknowledged. 6
HIGHER NATIONAL UNIT SPECIFICATION SUPPORT NOTES UNIT NUMBER: 2550727 UNIT TITLE: MECHANICAL ENGINEERING PRINCIPLES: STATICS AND DYNAMICS SUPPORT NOTES: This part of the unit specification is offered as guidance. None of the sections of the support notes is mandatory. NOTIONAL DESIGN LENGTH: SQA allocates a notional design length to a unit on the basis of time estimated for achievement of the stated standards by a candidate whose starting point is as described in the access statement. The notional design length for this unit is 40 hours. The use of notional design length for programme design and timetabling is advisory only. PURPOSE This is a general unit and is useful for candidates who are undertaking a program of study in engineering. Candidates will be able to acquire the basic skills required to carry out design and analysis of simple mechanical systems. The unit provides underpinning knowledge required for study of a wide variety of qualifications recognised by the professional engineering bodies (e.g. Incorporated Mechanical Engineer). CONTENT/CONTEXT Corresponding to outcomes: Outcome 1 Forces as vector quantities, resolution of forces into components, moments of forces, equations of equilibrium for 2-D problems, external and internal loading for plane, pin-jointed frames, determination of internal forces by calculation and by graphical methods, calculation of internal shear force and bending moment distribution in statically determinate beams carrying concentrated and uniformly distributed loading, construction of shear force and bending moment diagrams for such beams. Outcome 2 Concept of stress and strain, direct stress and shear stress, the tensile test for ductile and brittle materials, Hooke s law, elastic limit, modulus of elasticity. Poisson s ratio, yield and proof stress, ultimate stress, axial stress and strain in bars with uniform and stepped cross section under tensile and compressive loading, stress and strain in compound bars excluding self straining, riveted joints in single and double shear, bolted flanged couplings transmitting axial load and torque, blanking and piercing of various shapes from sheet material. 7
Outcome 3 Equations of angular motion for a body moving with constant angular acceleration about a fixed axis, relationship between linear and angular for a body moving with constant acceleration about a fixed axis. Outcome 4 Definition of particles and rigid bodies, mass and Newton s second law as applied to the motion of rigid bodies, friction and friction forces and torques acting on bodies, the motion of bodies and vehicles along the flat and on inclined surfaces, second moments of mass for discs and cylinders and the motion of bodies rotating about fixed axes, motion of connected linear and rotating systems. APPROACHES TO GENERATING EVIDENCE A mix of coursework and written evidence is recommended. In the case of coursework the submission must be the work of the individual and be confirmed as such. If any centre has computer based learning material, with an assessment facility, then assessment by this method is also acceptable. ASSESSMENT PROCEDURES Centres may use the Instruments of Assessment which are considered by the lecturers to be most appropriate. Outcome 2, performance criteria (a) and (b), should normally be assessed by a laboratory based coursework. All other performance criteria may be assessed by written test or coursework. Assessment of LO3 and LO4 should be integrated wherever possible. PROGRESSION access to the unit: Achievement of this unit would provide a sound basis for 2550797 Engineering Mechanics and Strength of Materials: General. REFERENCES 1. Guide to unit writing. 2. For a fuller discussion on assessment issues, please refer to SQA s Guide to Assessment. 3. Information for centres on SQA s operating procedures is contained in SQA s Guide to Procedures. 4. For details of other SQA publications, please consult SQA s publications list. 8
A support pack for this unit is available from SQA. Please call our Sales and Despatch section on 0141 242 2168 to check availability and costs. Quote product code C091. Copyright SQA 1997 Please note that this publication may be reproduced in whole or in part for educational purposes provided that: (i) (ii) no profit is derived from the reproduction; if reproduced in part, the source is acknowledged. 9