// Numbas version: finer_feedback_settings
{"name": "ElQ2 - Steady State & Step Response  - Randomised Variables Only", "extensions": [], "custom_part_types": [], "resources": [["question-resources/SbE_CC1_Q2c.png", "/srv/numbas/media/question-resources/SbE_CC1_Q2c.png"], ["question-resources/SbE_CC1_Q2b_aIYsTQF.png", "/srv/numbas/media/question-resources/SbE_CC1_Q2b_aIYsTQF.png"], ["question-resources/SbE_CC1_Q2d.png", "/srv/numbas/media/question-resources/SbE_CC1_Q2d.png"], ["question-resources/SbE_CC1_Q2a.png", "/srv/numbas/media/question-resources/SbE_CC1_Q2a.png"]], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"name": "ElQ2 - Steady State & Step Response  - Randomised Variables Only", "tags": [], "metadata": {"description": "<p>Question covering DC and Step response circuits</p>", "licence": "All rights reserved"}, "statement": "<h1 style=\"text-align: center;\">Steady State &amp; Step Response</h1>", "advice": "<p>See Spread Sheet</p>", "rulesets": {}, "extensions": [], "builtin_constants": {"e": true, "pi,\u03c0": true, "i": true, "j": false}, "constants": [], "variables": {"Q2b_R3": {"name": "Q2b_R3", "group": "Ungrouped variables", "definition": "q2b_rs1", "description": "<p>M</p>\n<p></p>", "templateType": "anything", "can_override": false}, "Q2b_Resistivity": {"name": "Q2b_Resistivity", "group": "Ungrouped variables", "definition": "random(640 .. 640#10)", "description": "<p>Resistivity of Silicon (&Omega;m)</p>", "templateType": "randrange", "can_override": false}, "Q2b_VS": {"name": "Q2b_VS", "group": "Ungrouped variables", "definition": "random(9 .. 12#1)", "description": "<p>Supply Voltage V</p>", "templateType": "randrange", "can_override": false}, "Q2b_R1": {"name": "Q2b_R1", "group": "Ungrouped variables", "definition": "random(4000000 .. 7000000#1000000)", "description": "<p>Resistance of R<sub>1</sub> in M&Omega;</p>", "templateType": "randrange", "can_override": false}, "Q2b_R2": {"name": "Q2b_R2", "group": "Ungrouped variables", "definition": "Q2b_R1", "description": "", "templateType": "anything", "can_override": false}, "Q2b_A1": {"name": "Q2b_A1", "group": "Ungrouped variables", "definition": "random(1 .. 2#1)", "description": "<p>Cross Sectional Area mm<sup>2</sup></p>", "templateType": "randrange", "can_override": false}, "Q2b_l1": {"name": "Q2b_l1", "group": "Ungrouped variables", "definition": "random(10 .. 10#1)", "description": "<p>length pf gauge mm</p>", "templateType": "randrange", "can_override": false}, "Q2b_Volume_of_Sample": {"name": "Q2b_Volume_of_Sample", "group": "Ungrouped variables", "definition": "dec(q2b_a1/1000000)*dec(Q2b_l1/1000)\n", "description": "", "templateType": "anything", "can_override": false}, "Q2b_l2": {"name": "Q2b_l2", "group": "Ungrouped variables", "definition": "random(10.1 .. 10.2#0.1)", "description": "<p>Length of sample after load is applied (mm)</p>", "templateType": "randrange", "can_override": false}, "Q2b_A2": {"name": "Q2b_A2", "group": "Ungrouped variables", "definition": "siground(dec((Q2b_Volume_of_Sample/(Q2b_l2/1000))*1000000),4)\n", "description": "<p>Cross Sectional Area of Guage when load is applied mm<sup>2</sup></p>", "templateType": "anything", "can_override": false}, "Q2b_RS1": {"name": "Q2b_RS1", "group": "Ungrouped variables", "definition": "siground(dec((Q2b_Resistivity*(Q2b_l1/1000))/(Q2b_a1/1000000)),4)\n", "description": "", "templateType": "anything", "can_override": false}, "Q2b_RS2": {"name": "Q2b_RS2", "group": "Ungrouped variables", "definition": "siground(dec((Q2b_Resistivity*(Q2b_l2/1000))/(Q2b_a2/1000000)),4)", "description": "", "templateType": "anything", "can_override": false}}, "variablesTest": {"condition": "", "maxRuns": 100}, "ungrouped_variables": ["Q2b_Resistivity", "Q2b_VS", "Q2b_R1", "Q2b_R2", "Q2b_R3", "Q2b_A1", "Q2b_l1", "Q2b_Volume_of_Sample", "Q2b_l2", "Q2b_A2", "Q2b_RS1", "Q2b_RS2"], "variable_groups": [], "functions": {}, "preamble": {"js": "", "css": ""}, "parts": [{"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "<p><strong>Part a. Circuit Symbols</strong></p>\n<p>For each of the symbols shown in the table, state the name and function of the device:&nbsp;</p>\n<p><img src=\"resources/question-resources/SbE_CC1_Q2a.png\" alt=\"Circuit Symbols\" width=\"376\" height=\"297\" style=\"display: block; margin-left: auto; margin-right: auto;\"/></p>\n<p><strong>[4 Marks]</strong></p>"}, {"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "<p><strong>Part b. Wheatstone Bridge Calculation</strong></p>\n<p>A Wheatstone Bridge is used to measure the change of resistance before &amp; while a load is applied to a gauge block made of silicon material with resistivity &rho; = {Q2b_Resistivity}&Omega;m.</p>\n<p><img src=\"resources/question-resources/SbE_CC1_Q2b_aIYsTQF.png\" alt=\"Wheatstone Bridge and Strain Gauge\" width=\"953\" height=\"378\" style=\"display: block; margin-left: auto; margin-right: auto;\"/></p>\n<p style=\"text-align: left;\"><strong>Circuit Varibles:&nbsp;</strong> V<sub>S</sub> = {Q2b_VS} V, R<sub>1</sub> = {siground({Q2b_R1}/1000000,2)} M&Omega;, &nbsp;R2 = {siground({Q2b_R2}/1000000,2)} M&Omega;, R3 = {siground({Q2b_R3}/1000000,2)} M&Omega;</p>\n<p></p>\n<p>The dimensions of the gauge <strong>before</strong> the load is applied are: Cross Sectional Area, A<sub>1</sub> &nbsp;= {Q2b_A1} mm<sup>2</sup>, length, l<sub>1</sub> = {Q2b_l1} mm.&nbsp; &nbsp;</p>\n<p>The dimensions of the gauge <strong>when</strong> the load is applied are: Cross Sectional Area, A<sub>2</sub>&nbsp;= {Q2b_A2} mm<sup>2</sup>, length, l<sub>2</sub> = {Q2b_l2} mm.&nbsp; &nbsp;</p>\n<ul>\n<li>Calculate the resistance (R<sub>S1</sub>) of the gauge <strong>before</strong> the load is applied.</li>\n<li>Calculate/determine the reading of <strong>V<sub>OUT</sub> </strong>for R<sub>S1</sub> &nbsp;</li>\n<li>Calculate the resistance (R<sub>S2</sub>) of the gauge <strong>when</strong> the load is applied.</li>\n<li>Calculate/determine the reading of <strong>V<sub>OUT</sub> </strong>for R<sub>S2</sub> &nbsp;</li>\n</ul>\n<p>SPICE circuit suitable for analysis:&nbsp; <a href=\"https://www.multisim.com/content/5LW69gJc6FJ3goGTgdhCsg/sbe-cc1-q1b/open/\">SbE CC1 Q1b (multisim.com)</a></p>\n<p><strong>[6 Marks]</strong></p>"}, {"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "<p><strong>Part c. Step Response</strong></p>\n<p>The circuit shows a Resistor and Capacitor Network as well as the charge/discharge plots of the Capacitor when the switch is closed and opened.</p>\n<p><img src=\"resources/question-resources/SbE_CC1_Q2c.png\" width=\"930\" height=\"286\" style=\"display: block; margin-left: auto; margin-right: auto;\"/></p>\n<p style=\"text-align: left;\"><strong>Circuit Varibles:</strong> V<sub>S</sub> = {5} V, V<sub>B</sub> = {2.5} V t<sub>ON </sub>={50} ms, t<sub>OFF </sub>={200} ms C<sub>1</sub> ={10} &mu;F , R<sub>1</sub> = {10} k&Omega;, R<sub>2</sub> = {2} k&Omega;</p>\n<p>&nbsp;</p>\n<p>Explain what is happening in the circuit.&nbsp; What is the relationship between the voltage across and current through the Capacitor.</p>\n<p>SPICE circuit suitable for analysis: <a href=\"https://www.multisim.com/content/9rW4rVU7peuxbZD6f2JvAk/sbe-cc1-q2c/open/\">SbE CC1 Q2c (multisim.com)</a></p>\n<p><strong>[8 Marks]</strong></p>"}, {"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "<p><strong>Part d. Circuit Analysis</strong></p>\n<p>The circuit shown is for a simple &lsquo;No Volt Release&rsquo; circuit configuration which is used as a safety feature on electrical equipment:</p>\n<p><img src=\"resources/question-resources/SbE_CC1_Q2d.png\" alt=\"No Volt Release\" width=\"429\" height=\"395\" style=\"display: block; margin-left: auto; margin-right: auto;\"/></p>\n<p>Analyse the operation of this circuit for the intended purpose. Ensure that you:</p>\n<ul>\n<li>Explain how the circuit functions including the function of the individual components.</li>\n<li>Identify any limitations of the circuit.</li>\n<li>Suggest improvements and/or augmentations to enhance the function.</li>\n</ul>\n<p>SPICE circuit suitable for analysis: <a href=\"https://everycircuit.com/circuit/5431791347040256/no-volt-release\">EveryCircuit - No Volt Release</a></p>\n<p>[12 Marks]</p>"}, {"type": "information", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "<p><strong>Part b. Wheatstone Bridge Calculation</strong></p>\n<p>A Wheatstone Bridge is used to measure the change of resistance before &amp; while a load is applied to a gauge block made of silicon material with resistivity &rho; = {Q2b_Resistivity}&Omega;m.</p>\n<p><img src=\"resources/question-resources/SbE_CC1_Q2b_aIYsTQF.png\" alt=\"Wheatstone Bridge and Strain Gauge\" width=\"953\" height=\"378\" style=\"display: block; margin-left: auto; margin-right: auto;\"/></p>\n<p style=\"text-align: left;\"><strong>Circuit Varibles:&nbsp;</strong> V<sub>S</sub> = {Q2b_VS} V, R<sub>1</sub> = {siground({Q2b_R1}/1000000,2)} M&Omega;, &nbsp;R2 = {siground({Q2b_R2}/1000000,2)} M&Omega;, R3 = {siground({Q2b_R3}/1000000,2)} M&Omega;</p>\n<p></p>\n<p>The dimensions of the gauge <strong>before</strong> the load is applied are: Cross Sectional Area, A<sub>1</sub> &nbsp;= {Q2b_A1} mm<sup>2</sup>, length, l<sub>1</sub> = {Q2b_l1} mm.&nbsp; &nbsp;</p>\n<p>The dimensions of the gauge <strong>when</strong> the load is applied are: Cross Sectional Area, A<sub>2</sub>&nbsp;= {Q2b_A2} mm<sup>2</sup>, length, l<sub>2</sub> = {Q2b_l2} mm.&nbsp; &nbsp;</p>\n<ul>\n<li>Calculate the resistance (R<sub>S1</sub>) of the gauge <strong>before</strong> the load is applied.</li>\n<li>Calculate/determine the reading of <strong>V<sub>OUT</sub> </strong>for R<sub>S1</sub> &nbsp;</li>\n<li>Calculate the resistance (R<sub>S2</sub>) of the gauge <strong>when</strong> the load is applied.</li>\n<li>Calculate/determine the reading of <strong>V<sub>OUT</sub> </strong>for R<sub>S2</sub> &nbsp;</li>\n</ul>\n<p>SPICE circuit suitable for analysis:&nbsp; <a href=\"https://www.multisim.com/content/5LW69gJc6FJ3goGTgdhCsg/sbe-cc1-q1b/open/\">SbE CC1 Q1b (multisim.com)</a></p>\n<p><strong>[6 Marks]</strong></p>"}], "partsMode": "all", "maxMarks": 0, "objectives": [], "penalties": [], "objectiveVisibility": "always", "penaltyVisibility": "always", "contributors": [{"name": "Robert Bauld", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/19446/"}]}]}], "contributors": [{"name": "Robert Bauld", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/19446/"}]}