Identify the errors (if any) in the student's free body diagrams.
\n{image('resources/question-resources/'+this['filename'])}
\n(#{index}. Click image to enlarge. )
\n", "advice": "{mistakes}
", "rulesets": {}, "extensions": [], "builtin_constants": {"e": true, "pi,\u03c0": true, "i": true}, "constants": [], "variables": {"mistakes": {"name": "mistakes", "group": "Ungrouped variables", "definition": "this['errors']", "description": "the student's mistakes
", "templateType": "anything", "can_override": false}, "choices": {"name": "choices", "group": "Ungrouped variables", "definition": "[\"Missing or incorrect labels\",\n\"Missing arrowheads\",\n\"Extra forces or moments\",\n\"Missing forces or moments\",\n\"Inconsistent forces at A\",\n\"Inconsistent forces at B\",\n\"Inconsistent forces at C\",\n\"Inconsistent forces at D\",\n\"Inconsistent moment\",\n\"Force with known direction shown as components\",\n\"Incorrect line of action\",\n\"No errors\"]\n", "description": "list of possible mistakes -- checkbox labels
", "templateType": "anything", "can_override": false}, "fbds": {"name": "fbds", "group": "Ungrouped variables", "definition": "json_decode(safe(\"[\\n {\\n \\\"filename\\\": \\\"fbd-0.png\\\",\\n \\\"errors\\\": [\\n \\\"Missing arrowheads\\\",\\n \\\"Extra forces or moments\\\",\\n \\\"Inconsistent forces at C\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-2.png\\\",\\n \\\"errors\\\": [\\n \\\"Extra forces or moments\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-3.png\\\",\\n \\\"errors\\\": [\\n \\\"Missing forces or moments\\\",\\n \\\"Incorrect line of action\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-7.png\\\",\\n \\\"errors\\\": [\\n \\\"Inconsistent forces at C\\\",\\n \\\"Incorrect line of action\\\",\\n \\\"Inconsistent forces at B\\\",\\n \\\"Missing forces or moments\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-6.png\\\",\\n \\\"errors\\\": [\\n \\\"Extra forces or moments\\\",\\n \\\"Inconsistent forces at C\\\",\\n \\\"Missing or incorrect labels\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-4.png\\\",\\n \\\"errors\\\": [\\n \\\"Extra forces or moments\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-5.png\\\",\\n \\\"errors\\\": [\\n \\\"No errors\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-16.png\\\",\\n \\\"errors\\\": [\\n \\\"Inconsistent forces at B\\\",\\n \\\"Extra forces or moments\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-17.png\\\",\\n \\\"errors\\\": [\\n \\\"Extra forces or moments\\\",\\n \\\"Incorrect line of action\\\",\\n \\\"Inconsistent forces at B\\\",\\n \\\"Inconsistent forces at C\\\",\\n \\\"Inconsistent forces at D\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-29.png\\\",\\n \\\"errors\\\": [\\n \\\"Inconsistent forces at B\\\",\\n \\\"Missing forces or moments\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-15.png\\\",\\n \\\"errors\\\": [\\n \\\"Inconsistent forces at A\\\",\\n \\\"Inconsistent forces at C\\\",\\n \\\"Missing forces or moments\\\",\\n \\\"Extra forces or moments\\\",\\n \\\"Incorrect line of action\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-14.png\\\",\\n \\\"errors\\\": [\\n \\\"No errors\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-28.png\\\",\\n \\\"errors\\\": [\\n \\\"Extra forces or moments\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-10.png\\\",\\n \\\"errors\\\": [\\n \\\"No errors\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-38.png\\\",\\n \\\"errors\\\": [\\n \\\"Inconsistent forces at A\\\",\\n \\\"Inconsistent forces at C\\\",\\n \\\"Missing forces or moments\\\",\\n \\\"Inconsistent forces at D\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-39.png\\\",\\n \\\"errors\\\": [\\n \\\"Inconsistent forces at A\\\",\\n \\\"Inconsistent forces at C\\\",\\n \\\"Inconsistent forces at D\\\",\\n \\\"Incorrect line of action\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-11.png\\\",\\n \\\"errors\\\": [\\n \\\"Extra forces or moments\\\",\\n \\\"Inconsistent forces at B\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-13.png\\\",\\n \\\"errors\\\": [\\n \\\"No errors\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-12.png\\\",\\n \\\"errors\\\": [\\n \\\"Missing forces or moments\\\",\\n \\\"Incorrect line of action\\\",\\n \\\"Missing or incorrect labels\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-37.png\\\",\\n \\\"errors\\\": [\\n \\\"Inconsistent forces at A\\\",\\n \\\"Incorrect line of action\\\",\\n \\\"Inconsistent forces at C\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-36.png\\\",\\n \\\"errors\\\": [\\n \\\"Inconsistent forces at A\\\",\\n \\\"Extra forces or moments\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-22.png\\\",\\n \\\"errors\\\": [\\n \\\"Missing or incorrect labels\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-34.png\\\",\\n \\\"errors\\\": [\\n \\\"Missing forces or moments\\\",\\n \\\"Inconsistent forces at B\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-20.png\\\",\\n \\\"errors\\\": [\\n \\\"Missing forces or moments\\\",\\n \\\"Extra forces or moments\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-21.png\\\",\\n \\\"errors\\\": [\\n \\\"Extra forces or moments\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-35.png\\\",\\n \\\"errors\\\": [\\n \\\"No errors\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-31.png\\\",\\n \\\"errors\\\": [\\n \\\"Extra forces or moments\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-25.png\\\",\\n \\\"errors\\\": [\\n \\\"No errors\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-19.png\\\",\\n \\\"errors\\\": [\\n \\\"Missing forces or moments\\\",\\n \\\"Incorrect line of action\\\",\\n \\\"Inconsistent forces at B\\\",\\n \\\"Extra forces or moments\\\",\\n \\\"Missing or incorrect labels\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-18.png\\\",\\n \\\"errors\\\": [\\n \\\"Inconsistent forces at A\\\",\\n \\\"Inconsistent forces at C\\\",\\n \\\"Missing or incorrect labels\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-24.png\\\",\\n \\\"errors\\\": [\\n \\\"Extra forces or moments\\\",\\n \\\"Inconsistent forces at B\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-26.png\\\",\\n \\\"errors\\\": [\\n \\\"Inconsistent forces at C\\\",\\n \\\"Incorrect line of action\\\",\\n \\\"Inconsistent forces at B\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-32.png\\\",\\n \\\"errors\\\": [\\n \\\"Extra forces or moments\\\",\\n \\\"Inconsistent forces at B\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-27.png\\\",\\n \\\"errors\\\": [\\n \\\"Missing forces or moments\\\",\\n \\\"Inconsistent forces at C\\\",\\n \\\"Inconsistent forces at A\\\",\\n \\\"Incorrect line of action\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-40.png\\\",\\n \\\"errors\\\": [\\n \\\"Extra forces or moments\\\",\\n \\\"Incorrect line of action\\\",\\n \\\"Missing forces or moments\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-8.png\\\",\\n \\\"errors\\\": [\\n \\\"Extra forces or moments\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-9.png\\\",\\n \\\"errors\\\": [\\n \\\"Inconsistent Moment\\\",\\n \\\"Incorrect line of action\\\",\\n \\\"Missing forces or moments\\\",\\n \\\"Inconsistent forces at B\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-41.png\\\",\\n \\\"errors\\\": [\\n \\\"force with known direction shown as components\\\",\\n \\\"Extra forces or moments\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-43.png\\\",\\n \\\"errors\\\": [\\n \\\"Inconsistent forces at C\\\",\\n \\\"Inconsistent forces at B\\\",\\n \\\"Missing forces or moments\\\",\\n \\\"Extra forces or moments\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-42.png\\\",\\n \\\"errors\\\": [\\n \\\"No errors\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-46.png\\\",\\n \\\"errors\\\": [\\n \\\"Inconsistent forces at D\\\",\\n \\\"Inconsistent forces at C\\\",\\n \\\"Inconsistent forces at A\\\",\\n \\\"Extra forces or moments\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-47.png\\\",\\n \\\"errors\\\": [\\n \\\"Missing or incorrect labels\\\",\\n \\\"Incorrect line of action\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-45.png\\\",\\n \\\"errors\\\": [\\n \\\"Extra forces or moments\\\"\\n ]\\n },\\n {\\n \\\"filename\\\": \\\"fbd-44.png\\\",\\n \\\"errors\\\": [\\n \\\"Missing arrowheads\\\"\\n ]\\n }\\n]\"))", "description": "array containing problem image file name and cooresponding errors
", "templateType": "json", "can_override": false}, "this": {"name": "this", "group": "Ungrouped variables", "definition": "fbds[index]", "description": "the current fbd and mistakes
", "templateType": "anything", "can_override": false}, "index": {"name": "index", "group": "Ungrouped variables", "definition": "random(0..length(fbds)-1)", "description": "", "templateType": "anything", "can_override": false}, "matrix": {"name": "matrix", "group": "Ungrouped variables", "definition": "map(if(indices(mistakes, d)=[],0,1),d,choices)", "description": "The marking matrix. 0 for don't tick, 1 for tick.
", "templateType": "anything", "can_override": false}}, "variablesTest": {"condition": "", "maxRuns": 100}, "ungrouped_variables": ["fbds", "this", "mistakes", "choices", "index", "matrix"], "variable_groups": [], "functions": {}, "preamble": {"js": "", "css": "img{width:600px;}"}, "parts": [{"type": "m_n_2", "useCustomName": false, "customName": "", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "mark:\n assert(marks>0,correct()); // any answer is correct when 0 marks are available\n assert(numTicks>0,\n warn(translate(\"part.marking.nothing entered\"));\n fail(translate(\"part.marking.nothing entered\"))\n );\n apply(same_ticks)\n\nshould_be_ticked (A chocie should be ticked if it's awarded ap ositive number of marks):\n map(map(y>0,y,row),row,settings[\"matrix\"])\n\nsame_ticks (Did the student tick the same choices as the expected answer?):\n correctif(studentanswer=should_be_ticked)\n\n", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "Check {length(mistakes)} {pluralise(length(mistakes),\"box\",\"boxes\")}.
", "minMarks": "0", "maxMarks": "10", "shuffleChoices": false, "displayType": "checkbox", "displayColumns": "2", "minAnswers": "length(mistakes)", "maxAnswers": "length(mistakes)", "warningType": "none", "showCellAnswerState": true, "markingMethod": "all-or-nothing", "choices": "choices", "matrix": "matrix"}], "partsMode": "all", "maxMarks": 0, "objectives": [], "penalties": [], "objectiveVisibility": "always", "penaltyVisibility": "always", "contributors": [{"name": "William Haynes", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/2530/"}]}]}], "contributors": [{"name": "William Haynes", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/2530/"}]}