The student is shown two radio choices: \"Yes\" and \"No\". One of them is correct.
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\n\nLet’s work through this assignment in parts:
", "advice": "", "rulesets": {}, "extensions": ["quantities"], "variables": {"k": {"name": "k", "group": "Ungrouped variables", "definition": "random(0.12 .. 0.18#0.01)", "description": "", "templateType": "randrange"}, "Di": {"name": "Di", "group": "Ungrouped variables", "definition": "random(0.13 .. 0.15#0.01)", "description": "", "templateType": "randrange"}, "Do": {"name": "Do", "group": "Ungrouped variables", "definition": "random(0.17 .. 0.2#0.01)", "description": "", "templateType": "randrange"}, "ho": {"name": "ho", "group": "Ungrouped variables", "definition": "random(1400 .. 1600#10)", "description": "", "templateType": "randrange"}, "m": {"name": "m", "group": "Ungrouped variables", "definition": "random(0.015 .. 0.03#0.001)", "description": "", "templateType": "randrange"}, "Rp": {"name": "Rp", "group": "Ungrouped variables", "definition": "ln(Do/Di)/(2*pi*k)", "description": "", "templateType": "anything"}, "Ro": {"name": "Ro", "group": "Ungrouped variables", "definition": "1/(ho*Pi*Do)", "description": "", "templateType": "anything"}, "Tmi": {"name": "Tmi", "group": "Ungrouped variables", "definition": "29", "description": "", "templateType": "number"}, "Tmo": {"name": "Tmo", "group": "Ungrouped variables", "definition": "21", "description": "", "templateType": "number"}, "Tinf": {"name": "Tinf", "group": "Ungrouped variables", "definition": "17", "description": "", "templateType": "number"}, "Ak": {"name": "Ak", "group": "Ungrouped variables", "definition": "273 + ((Tmi + Tmo) / 2)", "description": "", "templateType": "anything"}, "Re": {"name": "Re", "group": "Ungrouped variables", "definition": "(4*m)/(pi*Di*mu)", "description": "", "templateType": "anything"}, "mu": {"name": "mu", "group": "Ungrouped variables", "definition": "183.6*(10^(-7))", "description": "", "templateType": "anything"}, "Nu": {"name": "Nu", "group": "Ungrouped variables", "definition": "0.023*(Re^(4/5))*(0.707^0.3)", "description": "", "templateType": "anything"}, "hi": {"name": "hi", "group": "Ungrouped variables", "definition": "(0.0261*Nu)/Di", "description": "", "templateType": "anything"}, "u": {"name": "u", "group": "Ungrouped variables", "definition": "1/(((ln(Do/Di))/(2*pi*k))+R1+(1/(ho*pi*Do)))", "description": "", "templateType": "anything"}, "L": {"name": "L", "group": "Ungrouped variables", "definition": "-((ln(1/3))/(u/(m*1007)))", "description": "", "templateType": "anything"}, "R1": {"name": "R1", "group": "Ungrouped variables", "definition": "1/(hi*pi*Di)", "description": "", "templateType": "anything"}, "cc": {"name": "cc", "group": "Ungrouped variables", "definition": "1/(Rp+Ro+R1)", "description": "", "templateType": "anything"}}, "variablesTest": {"condition": "", "maxRuns": 100}, "ungrouped_variables": ["Tmi", "Tmo", "Tinf", "mu", "k", "Di", "Do", "ho", "m", "Rp", "Ro", "Ak", "Re", "Nu", "hi", "R1", "u", "L", "cc"], "variable_groups": [], "functions": {}, "preamble": {"js": "", "css": ""}, "parts": [{"type": "1_n_2", "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": "What mode of heat transfer is present between the air pipe outer surface and water?
", "minMarks": 0, "maxMarks": 0, "shuffleChoices": false, "displayType": "radiogroup", "displayColumns": 0, "showCellAnswerState": true, "choices": ["Conduction
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\nWhat mechanism of heat transfer is present between the air pipe outer surface and its inner surface?
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", "settings": {"correct_answer_expr": "false"}}, {"type": "yes-no", "useCustomName": false, "customName": "", "marks": 1, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "Do we have a uniform surface temperature or a uniform surface heat flux condition on the outer surface of the pipe?
\nIf we were to use a U value between the air in the pipe and the water outside of it, what would it include? (select all that applies)
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", "minValue": "Ro-0.0008", "maxValue": "Ro+0.0008", "correctAnswerFraction": false, "allowFractions": false, "mustBeReduced": false, "mustBeReducedPC": 0, "showFractionHint": true, "notationStyles": ["plain", "en", "si-en"], "correctAnswerStyle": "plain"}, {"type": "numberentry", "useCustomName": false, "customName": "", "marks": "3", "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "We need air flow properties. At what temperature, do we look up values? Provide your answer in K.
", "minValue": "297", "maxValue": "299", "correctAnswerFraction": false, "allowFractions": false, "mustBeReduced": false, "mustBeReducedPC": 0, "showFractionHint": true, "notationStyles": ["plain", "en", "si-en"], "correctAnswerStyle": "plain"}, {"type": "numberentry", "useCustomName": false, "customName": "", "marks": "3", "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "What is the air specific heat that we use in our calculations? (only add the number, but not the unit in J/kg.K)
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", "minValue": "0.0259", "maxValue": "0.0263", "correctAnswerFraction": false, "allowFractions": false, "mustBeReduced": false, "mustBeReducedPC": 0, "showFractionHint": true, "notationStyles": ["plain", "en", "si-en"], "correctAnswerStyle": "plain"}, {"type": "numberentry", "useCustomName": false, "customName": "", "marks": "3", "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "What is the air Pr that we use in our calculations? (add the number in three significant figures.)
", "minValue": "0.705", "maxValue": "0.709", "correctAnswerFraction": false, "allowFractions": false, "mustBeReduced": false, "mustBeReducedPC": 0, "showFractionHint": true, "notationStyles": ["plain", "en", "si-en"], "correctAnswerStyle": "plain"}, {"type": "numberentry", "useCustomName": false, "customName": "", "marks": "3", "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "Calculate the Reynolds number for the air flow.
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", "minMarks": 0, "maxMarks": 0, "shuffleChoices": false, "displayType": "radiogroup", "displayColumns": 0, "showCellAnswerState": true, "choices": ["laminar", "turbulent"], "matrix": ["0", "2"], "distractors": ["", ""]}, {"type": "numberentry", "useCustomName": false, "customName": "", "marks": "2", "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "Assuming a fully developed flow throughout the pipe, what is the Nu number for the air flow?
", "minValue": "Nu-0.5", "maxValue": "Nu+0.5", "correctAnswerFraction": false, "allowFractions": false, "mustBeReduced": false, "mustBeReducedPC": 0, "showFractionHint": true, "notationStyles": ["plain", "en", "si-en"], "correctAnswerStyle": "plain"}, {"type": "numberentry", "useCustomName": false, "customName": "", "marks": "3", "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "Calculate the convection coefficient between the air flow and the pipe inner surface.
", "minValue": "hi-0.05", "maxValue": "hi+0.05", "correctAnswerFraction": false, "allowFractions": false, "mustBeReduced": false, "mustBeReducedPC": 0, "showFractionHint": true, "notationStyles": ["plain", "en", "si-en"], "correctAnswerStyle": "plain"}, {"type": "numberentry", "useCustomName": false, "customName": "", "marks": "3", "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "Calculate the thermal resistance, R’, between the air flow and the pipe inner surface.
", "minValue": "R1-0.01", "maxValue": "R1+0.01", "correctAnswerFraction": false, "allowFractions": false, "mustBeReduced": false, "mustBeReducedPC": 0, "showFractionHint": true, "notationStyles": ["plain", "en", "si-en"], "correctAnswerStyle": "plain"}, {"type": "numberentry", "useCustomName": false, "customName": "", "marks": "3", "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "We know UAs = 1 / R and R’ = R/L. Use this to calculate UAs/L and enter it below (provide the number only, with three decimal figures, in W/K):
", "minValue": "u-0.05", "maxValue": "u+0.05", "correctAnswerFraction": false, "allowFractions": false, "mustBeReduced": false, "mustBeReducedPC": 0, "showFractionHint": true, "notationStyles": ["plain", "en", "si-en"], "correctAnswerStyle": "plain"}, {"type": "numberentry", "useCustomName": false, "customName": "", "marks": "3", "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "What pipe length L is needed to provide a discharge temperature of Tm,o = 21°C?
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