// Numbas version: exam_results_page_options {"name": "Maria's copy of Jo-Ann's draft copy of Area under a curve by integration", "extensions": ["geogebra", "weh", "quantities"], "custom_part_types": [{"source": {"pk": 19, "author": {"name": "William Haynes", "pk": 2530}, "edit_page": "/part_type/19/edit"}, "name": "Engineering Accuracy with units", "short_name": "engineering-answer", "description": "

A value with units marked right if within an adjustable % error of the correct value.  Marked close if within a wider margin of error.

", "help_url": "", "input_widget": "string", "input_options": {"correctAnswer": "siground(settings['correctAnswer'],4)", "hint": {"static": true, "value": ""}, "allowEmpty": {"static": true, "value": true}}, "can_be_gap": true, "can_be_step": true, "marking_script": "mark:\nswitch( \n right and good_units and right_sign, add_credit(1.0,'Correct.'),\n right and good_units and not right_sign, add_credit(settings['C2'],'Wrong sign.'),\n right and right_sign and not good_units, add_credit(settings['C2'],'Correct value, but wrong or missing units.'),\n close and good_units, add_credit(settings['C1'],'Close.'),\n close and not good_units, add_credit(settings['C3'],'Answer is close, but wrong or missing units.'),\n incorrect('Wrong answer.')\n)\n\n\ninterpreted_answer:\nqty(student_scalar, student_units)\n\n\n\ncorrect_quantity:\nsettings[\"correctAnswer\"]\n\n\n\ncorrect_units:\nunits(correct_quantity)\n\n\nallowed_notation_styles:\n[\"plain\",\"en\"]\n\nmatch_student_number:\nmatchnumber(studentAnswer,allowed_notation_styles)\n\nstudent_scalar:\nmatch_student_number[1]\n\nstudent_units:\nreplace_regex('ohms','ohm',\n replace_regex('\u00b0', ' deg',\n replace_regex('-', ' ' ,\n studentAnswer[len(match_student_number[0])..len(studentAnswer)])),\"i\")\n\ngood_units:\ntry(\ncompatible(quantity(1, student_units),correct_units),\nmsg,\nfeedback(msg);false)\n\n\nstudent_quantity:\nswitch(not good_units, \n student_scalar * correct_units, \n not right_sign,\n -quantity(student_scalar, student_units),\n quantity(student_scalar,student_units)\n)\n \n\n\npercent_error:\ntry(\nscalar(abs((correct_quantity - student_quantity)/correct_quantity))*100 \n,msg,\nif(student_quantity=correct_quantity,0,100))\n \n\nright:\npercent_error <= settings['right']\n\n\nclose:\nright_sign and percent_error <= settings['close']\n\nright_sign:\nsign(student_scalar) = sign(correct_quantity)", "marking_notes": [{"name": "mark", "description": "This is the main marking note. It should award credit and provide feedback based on the student's answer.", "definition": "switch( \n right and good_units and right_sign, add_credit(1.0,'Correct.'),\n right and good_units and not right_sign, add_credit(settings['C2'],'Wrong sign.'),\n right and right_sign and not good_units, add_credit(settings['C2'],'Correct value, but wrong or missing units.'),\n close and good_units, add_credit(settings['C1'],'Close.'),\n close and not good_units, add_credit(settings['C3'],'Answer is close, but wrong or missing units.'),\n incorrect('Wrong answer.')\n)\n"}, {"name": "interpreted_answer", "description": "A value representing the student's answer to this part.", "definition": "qty(student_scalar, student_units)\n\n"}, {"name": "correct_quantity", "description": "", "definition": "settings[\"correctAnswer\"]\n\n"}, {"name": "correct_units", "description": "", "definition": "units(correct_quantity)\n"}, {"name": "allowed_notation_styles", "description": "", "definition": "[\"plain\",\"en\"]"}, {"name": "match_student_number", "description": "", "definition": "matchnumber(studentAnswer,allowed_notation_styles)"}, {"name": "student_scalar", "description": "", "definition": "match_student_number[1]"}, {"name": "student_units", "description": "

Modify the unit portion of the student's answer by

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1. replacing \"ohms\" with \"ohm\"  case insensitive

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2. replacing '-' with ' ' 

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3. replacing '°' with ' deg' 

\n

to allow answers like 10 ft-lb and 30°

", "definition": "replace_regex('ohms','ohm',\n replace_regex('\u00b0', ' deg',\n replace_regex('-', ' ' ,\n studentAnswer[len(match_student_number[0])..len(studentAnswer)])),\"i\")"}, {"name": "good_units", "description": "", "definition": "try(\ncompatible(quantity(1, student_units),correct_units),\nmsg,\nfeedback(msg);false)\n"}, {"name": "student_quantity", "description": "

This fixes the student answer for two common errors.  

\n

If student_units are wrong  - replace with correct units

\n

If student_scalar has the wrong sign - replace with right sign

\n

If student makes both errors, only one gets fixed.

", "definition": "switch(not good_units, \n student_scalar * correct_units, \n not right_sign,\n -quantity(student_scalar, student_units),\n quantity(student_scalar,student_units)\n)\n \n"}, {"name": "percent_error", "description": "", "definition": "try(\nscalar(abs((correct_quantity - student_quantity)/correct_quantity))*100 \n,msg,\nif(student_quantity=correct_quantity,0,100))\n "}, {"name": "right", "description": "", "definition": "percent_error <= settings['right']\n"}, {"name": "close", "description": "

Only marked close if the student actually has the right sign.

", "definition": "right_sign and percent_error <= settings['close']"}, {"name": "right_sign", "description": "", "definition": "sign(student_scalar) = sign(correct_quantity) "}], "settings": [{"name": "correctAnswer", "label": "Correct Quantity.", "help_url": "", "hint": "The correct answer given as a JME quantity.", "input_type": "code", "default_value": "", "evaluate": true}, {"name": "right", "label": "% Accuracy for right.", "help_url": "", "hint": "Question will be considered correct if the scalar part of the student's answer is within this % of correct value.", "input_type": "code", "default_value": "0.2", "evaluate": true}, {"name": "close", "label": "% Accuracy for close.", "help_url": "", "hint": "Question will be considered close if the scalar part of the student's answer is within this % of correct value.", "input_type": "code", "default_value": "1.0", "evaluate": true}, {"name": "C1", "label": "Close with units.", "help_url": "", "hint": "Partial Credit for close value with appropriate units.  if correct answer is 100 N and close is ±1%,
99  N is accepted.", "input_type": "percent", "default_value": "75"}, {"name": "C2", "label": "No units or wrong sign", "help_url": "", "hint": "Partial credit for forgetting units or using wrong sign.
If the correct answer is 100 N, both 100 and -100 N are accepted.", "input_type": "percent", "default_value": "50"}, {"name": "C3", "label": "Close, no units.", "help_url": "", "hint": "Partial Credit for close value but forgotten units.
This value would be close if the expected units were provided.  If the correct answer is 100 N, and close is ±1%,
99 is accepted.", "input_type": "percent", "default_value": "25"}], "public_availability": "always", "published": true, "extensions": ["quantities"]}], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"functions": {}, "parts": [{"type": "gapfill", "customMarkingAlgorithm": "", "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacementStrategy": "originalfirst", "prompt": "

Determine the points where the curve crosses the axes.

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$h$ = [[0]] {qty(C,units)}

\n

$a$ = [[1]] {siground(root1,4)}

", "scripts": {}, "variableReplacements": [], "gaps": [{"scripts": {}, "unitTests": [], "type": "engineering-answer", "customMarkingAlgorithm": "", "marks": "2", "settings": {"C1": "75", "close": "1.0", "right": "0.2", "C3": "25", "correctAnswer": "qty(C,units)", "C2": "50"}, "extendBaseMarkingAlgorithm": true, "showCorrectAnswer": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "showFeedbackIcon": true}, {"scripts": {}, "unitTests": [], "type": "engineering-answer", "customMarkingAlgorithm": "", "marks": "2", "settings": {"C1": "75", "close": "1.0", "right": "0.2", "C3": "25", "correctAnswer": "root1", "C2": "50"}, "extendBaseMarkingAlgorithm": true, "showCorrectAnswer": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "showFeedbackIcon": true}], "marks": 0, "unitTests": [], "extendBaseMarkingAlgorithm": true, "sortAnswers": false}, {"type": "gapfill", "customMarkingAlgorithm": "", "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacementStrategy": "originalfirst", "prompt": "

Set up and evaluate the integral equation below to find the area under the curve.

\n

$\\begin{align} A &= \\int_0^a y\\, dx \\\\ \\vdots\\end{align}$

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$A$ = [[0]]  {siground(area,4)}

", "scripts": {}, "variableReplacements": [], "gaps": [{"scripts": {}, "unitTests": [], "type": "engineering-answer", "customMarkingAlgorithm": "", "marks": "6", "settings": {"C1": "75", "close": "1.0", "right": "0.2", "C3": "25", "correctAnswer": "area", "C2": "50"}, "extendBaseMarkingAlgorithm": true, "showCorrectAnswer": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "showFeedbackIcon": true}], "marks": 0, "unitTests": [], "extendBaseMarkingAlgorithm": true, "sortAnswers": false}], "extensions": ["geogebra", "quantities", "weh"], "tags": [], "statement": "

Given the function $\\color{red}{y=\\simplify[!noleadingminus,unitfactor]{{A} x^2 + {B} x + {C}}}$, determine the area under the curve from the y-axis to the point where the curve crosses the positive x-axis.  The x- and y- coordinates are in [{units}]. Give your answers correct to at least 3 significant figures and include the correct units (nb: if you see 'in' or 'mm' etc. it means inches, millimetres etc. Write the units as they appear in the question).

\n

{geogebra_applet('nuhzkzqp',[['a',A],['b',B],['c',C]])}

\n

\n

", "name": "Maria's copy of Jo-Ann's draft copy of Area under a curve by integration", "advice": "
    \n
  1. To find the point where the curve crosses the y-axis, set x = 0 and solve for y.
  2. \n
  3. To find the point where the curve crosses the positive x-axis, set y to zero and solve for x using the quadratic formula.
  4. \n
  5. To find the area under the curve, divide the shaded area into vertical differential strips where $dA = y\\, dx$ then integrate between the horizontal limits to find the area.
  6. \n
\n

$\\begin{align}A &= \\int dA \\\\&= \\int_0^a y\\,dx \\\\&= \\int_0^a(\\simplify[!noleadingminus,unitfactor]{{A} x^2 + {B} x + {C}})\\, dx\\\\& = \\left[ \\simplify[unitfactor,collectnumbers]{{A} x^3/3 + {B} x^2/3 + {C}x}\\right]_0^\\var{scalar(siground(root1,4))}\\\\&=\\var{siground(area,4)}\\end{align}$

", "variable_groups": [], "preamble": {"css": "", "js": ""}, "rulesets": {}, "metadata": {"licence": "Creative Commons Attribution-NonCommercial 4.0 International", "description": "

Find roots and the area under a parabola

"}, "variables": {"B": {"name": "B", "definition": "random(1..4)", "templateType": "anything", "description": "", "group": "Ungrouped variables"}, "units": {"name": "units", "definition": "random('in','ft','mm','cm')", "templateType": "anything", "description": "", "group": "Ungrouped variables"}, "root1": {"name": "root1", "definition": "qty((-b - sqrt(b^2-4 a c))/(2 a),units)", "templateType": "anything", "description": "", "group": "Ungrouped variables"}, "area": {"name": "area", "definition": "let(x,scalar(root1), qty(A x^3/3 + B x^2/2 + C x,units)) qty(units)", "templateType": "anything", "description": "", "group": "Ungrouped variables"}, "A": {"name": "A", "definition": "random(-0.5..-2#0.5)", "templateType": "anything", "description": "", "group": "Ungrouped variables"}, "debug": {"name": "debug", "definition": "false", "templateType": "anything", "description": "", "group": "Ungrouped variables"}, "C": {"name": "C", "definition": "random(0..3)+0.5", "templateType": "anything", "description": "", "group": "Ungrouped variables"}}, "ungrouped_variables": ["A", "B", "C", "root1", "area", "units", "debug"], "variablesTest": {"maxRuns": 100, "condition": ""}, "type": "question", "contributors": [{"name": "Ann Smith", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/2295/"}, {"name": "William Haynes", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/2530/"}, {"name": "Jo-Ann Lyons", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/2630/"}, {"name": "Maria Aneiros", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/3388/"}]}]}], "contributors": [{"name": "Ann Smith", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/2295/"}, {"name": "William Haynes", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/2530/"}, {"name": "Jo-Ann Lyons", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/2630/"}, {"name": "Maria Aneiros", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/3388/"}]}