// Numbas version: exam_results_page_options {"name": "22. Distributed Loads", "metadata": {"description": "

Homework set. Uniformly and uniformly varying distributed loads.

", "licence": "Creative Commons Attribution-ShareAlike 4.0 International"}, "duration": 0, "percentPass": 0, "showQuestionGroupNames": false, "shuffleQuestionGroups": false, "showstudentname": true, "question_groups": [{"name": "Group", "pickingStrategy": "all-ordered", "pickQuestions": 1, "questionNames": ["", "", ""], "variable_overrides": [[], [], []], "questions": [{"name": "Reactions for beam with uniformly distributed load", "extensions": ["geogebra", "quantities", "weh"], "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

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

2. replacing '-' with ' '

3. replacing '°' with ' deg'

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.

If student_units are wrong - replace with correct units

If student_scalar has the wrong sign - replace with right sign

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}, "contributors": [{"name": "William Haynes", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/2530/"}], "tags": [], "metadata": {"description": "

Find the reactions for a beam with a uniformly distributed load.

", "licence": "Creative Commons Attribution-NonCommercial 4.0 International"}, "statement": "

{geogebra_applet('kuhdcgxv',[ 'a': scalar(A),'b': scalar(B),'c': scalar(C),'d': scalar(D),'l': scalar(L)])}

A {L} long beam is subjected to a {loading} uniformly distributed load. Assume the weight of the beam is negligible.

w: {loading} W: {w} $F_A$: {FA} $F_B$ {FB}

", "advice": "

To solve, replace the distributed load with an equivalent concentrated load. The equivalent concentrated load acts at the centroid of the rectangle, and its magnitude is the \"area\" of the rectangle.

Once replaced, draw a free body diagram; then take moments at A to find B and vice-versa. Check your work by applying $\\Sigma F_y = 0$.

", "rulesets": {}, "variables": {"x": {"name": "x", "group": "Ungrouped variables", "definition": "(C+D)/2", "description": "

midpoint of load

", "templateType": "anything"}, "loading": {"name": "loading", "group": "inputs", "definition": "qty(random(1,2,3,4,5,6)* random(10, 20, 50, 100),units[0]+\"/\"+units[1])", "description": "

magnitude of distributed loading [force/length]

", "templateType": "anything"}, "D": {"name": "D", "group": "inputs", "definition": "qty(random(scalar(C)..scalar(L)),units[1])", "description": "

distributed load ends here

D-C > 3 and B-A > L/2 and A<>C and B<>D

", "templateType": "anything"}, "C": {"name": "C", "group": "inputs", "definition": "qty(random(0..scalar(L)),units[1])", "description": "

distributed load starts here

", "templateType": "anything"}, "FA": {"name": "FA", "group": "Ungrouped variables", "definition": "W-FB", "description": "

reaction at A

", "templateType": "anything"}, "B": {"name": "B", "group": "inputs", "definition": "qty(random(scalar(A)..scalar(L)),units[1])", "description": "

location of right hand support

", "templateType": "anything"}, "W": {"name": "W", "group": "Ungrouped variables", "definition": "loading * (D-C)", "description": "

Downward force

", "templateType": "anything"}, "L": {"name": "L", "group": "inputs", "definition": "qty(random(8,10,12,14,16),units[1])", "description": "

length of beam

", "templateType": "anything"}, "debug": {"name": "debug", "group": "Ungrouped variables", "definition": "false", "description": "", "templateType": "anything"}, "FB": {"name": "FB", "group": "Ungrouped variables", "definition": "(x-A) * W / (B-A)\n", "description": "

reaction at B

", "templateType": "anything"}, "units": {"name": "units", "group": "inputs", "definition": "random(['lb','ft'],['N','m'])", "description": "", "templateType": "anything"}, "A": {"name": "A", "group": "inputs", "definition": "qty(random(0..scalar(L)/2),units[1])", "description": "

location of left hand support

", "templateType": "anything"}}, "variablesTest": {"condition": "D-C > qty(3,units[1]) and B-A > L/2 and A<>C and B<>D", "maxRuns": 100}, "ungrouped_variables": ["W", "FB", "x", "FA", "debug"], "variable_groups": [{"name": "inputs", "variables": ["A", "B", "C", "D", "loading", "units", "L"]}], "functions": {}, "preamble": {"js": "", "css": ""}, "parts": [{"type": "gapfill", "useCustomName": true, "customName": "Reactions", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "

Determine the reactions at $A$ and $B$.

$A$ = [[0]] $B$ = [[1]]

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

Modify the unit portion of the student's answer by

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

2. replacing '-' with ' '

3. replacing '°' with ' deg'

to allow answers like 10 ft-lb and 30°

This fixes the student answer for two common errors.

If student_units are wrong - replace with correct units

If student_scalar has the wrong sign - replace with right sign

If student makes both errors, only one gets fixed.

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": [["question-resources/dist-load.ggb", "/srv/numbas/media/question-resources/dist-load.ggb"]], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "contributors": [{"name": "William Haynes", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/2530/"}], "tags": ["mechanics, statics, reactions, distributed load, uniformly varying load"], "metadata": {"description": "

Find the reactions for a beam with a uniformly varying distributed load.

", "licence": "Creative Commons Attribution-NonCommercial 4.0 International"}, "statement": "

{applet}

A {qty(L, units[1]) } long beam is subjected to a load which varies uniformly from {qty(wc * loading,units[0])} at $C$ to {qty(wd * loading,units[0])} at $D$. The beam itself weighs {qty(w_b,units[0] + \"/\" + units[1])}.

W: {w} beam: {wb} xbar: {x} check: {check}

$F_A$: {precround(FA,4)} $F_B$ {precround(FB,4)}

", "advice": "

To solve, divide the trapazoid into a rectangle and a triangle or two triangles, then replace each with an equivalent concentrated load. The equivalent concentrated load acts at the centroid of each shape, and its magnitude is the \"area\" of the shape.
Treat the beam as a uniformly distributed load, and place the weight of the beam at the center.
Once replaced, draw a free body diagram; then take moments at A to find B and vice-versa. Check your work by applying $\\Sigma F_y = 0$.

", "rulesets": {}, "builtin_constants": {"e": true, "pi,\u03c0": true, "i": true}, "constants": [], "variables": {"D": {"name": "D", "group": "inputs", "definition": "random(C+3..L except B)", "description": "

distributed load ends here

", "templateType": "anything", "can_override": false}, "L": {"name": "L", "group": "inputs", "definition": "random(8,10,12,14)", "description": "

length of beam

", "templateType": "anything", "can_override": false}, "units": {"name": "units", "group": "inputs", "definition": "random(['lb','ft'],['kN','m'])", "description": "", "templateType": "anything", "can_override": false}, "loading": {"name": "loading", "group": "inputs", "definition": "random(10..50#10)", "description": "

distributed loading [force/length]

", "templateType": "anything", "can_override": false}, "FA": {"name": "FA", "group": "Ungrouped variables", "definition": "(W + WB)-FB", "description": "

reaction at A

", "templateType": "anything", "can_override": false}, "debug": {"name": "debug", "group": "Ungrouped variables", "definition": "false", "description": "", "templateType": "anything", "can_override": false}, "wc": {"name": "wc", "group": "inputs", "definition": "random(0..2#0.5 except 0.5)", "description": "

load at c (scaled)

", "templateType": "anything", "can_override": false}, "W": {"name": "W", "group": "Ungrouped variables", "definition": "precround(loading * (wc+wd)/2 * (D-C),5)", "description": "

Downward force due to load

", "templateType": "anything", "can_override": false}, "B": {"name": "B", "group": "inputs", "definition": "random(L-3..L)", "description": "

location of right hand support

", "templateType": "anything", "can_override": false}, "C": {"name": "C", "group": "inputs", "definition": "random(0..5 except A)", "description": "

distributed load starts here

", "templateType": "anything", "can_override": false}, "A": {"name": "A", "group": "inputs", "definition": "0", "description": "

location of left hand support

", "templateType": "anything", "can_override": false}, "wd": {"name": "wd", "group": "inputs", "definition": "random(0..2#0.5 except 0.5)", "description": "

loading at d scaled

", "templateType": "anything", "can_override": false}, "x": {"name": "x", "group": "Ungrouped variables", "definition": "C + (wc / 6 + wd/ 3)(D-C) * 2/(wc+wd)", "description": "

midpoint of load

", "templateType": "anything", "can_override": false}, "FB": {"name": "FB", "group": "Ungrouped variables", "definition": "precround(((x-A) * W + (CG-A) * WB) / (B-A),5)\n", "description": "

reaction at B

", "templateType": "anything", "can_override": false}, "w_b": {"name": "w_b", "group": "inputs", "definition": "siground(random(0.1..1 #0.1) loading,3)", "description": "

Weight of the beam in W/L units

", "templateType": "anything", "can_override": false}, "CG": {"name": "CG", "group": "Ungrouped variables", "definition": "L/2", "description": "

center of the beam

", "templateType": "anything", "can_override": false}, "WB": {"name": "WB", "group": "Ungrouped variables", "definition": "w_b L ", "description": "

Weight of the beam itself

", "templateType": "anything", "can_override": false}, "check": {"name": "check", "group": "Ungrouped variables", "definition": "(W + WB)= (FA+FB)", "description": "", "templateType": "anything", "can_override": false}, "params": {"name": "params", "group": "ggb", "definition": "[ a: A, b: B, c: C, d: D, l: L, w_c: wc, w_d: wd ]", "description": "", "templateType": "anything", "can_override": false}, "applet": {"name": "applet", "group": "ggb", "definition": "geogebra_file('dist-load.ggb',params)", "description": "", "templateType": "anything", "can_override": false}, "points": {"name": "points", "group": "inputs", "definition": "sort(deal(L)[0..2])", "description": "", "templateType": "anything", "can_override": false}}, "variablesTest": {"condition": "D-C > L/3 and \nwc<>wd", "maxRuns": 100}, "ungrouped_variables": ["W", "FB", "x", "FA", "debug", "CG", "WB", "check"], "variable_groups": [{"name": "inputs", "variables": ["A", "B", "C", "D", "loading", "units", "L", "wc", "wd", "w_b", "points"]}, {"name": "ggb", "variables": ["params", "applet"]}], "functions": {}, "preamble": {"js": "", "css": ""}, "parts": [{"type": "gapfill", "useCustomName": true, "customName": "Find Reactions", "marks": 0, "scripts": {}, "customMarkingAlgorithm": "", "extendBaseMarkingAlgorithm": true, "unitTests": [], "showCorrectAnswer": true, "showFeedbackIcon": true, "variableReplacements": [], "variableReplacementStrategy": "originalfirst", "nextParts": [], "suggestGoingBack": false, "adaptiveMarkingPenalty": 0, "exploreObjective": null, "prompt": "

Determine the reactions at $A$ and $B$.

$A$ = [[0]] $B$ = [[1]]

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

Modify the unit portion of the student's answer by

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

2. replacing '-' with ' '

3. replacing '°' with ' deg'

to allow answers like 10 ft-lb and 30°

This fixes the student answer for two common errors.

If student_units are wrong - replace with correct units

If student_scalar has the wrong sign - replace with right sign

If student makes both errors, only one gets fixed.

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

Find the reactions of a simply-supported beam with a trapazoidal distributed load.

", "licence": "Creative Commons Attribution-ShareAlike 4.0 International"}, "statement": "

{geogebra_applet('xgjx2s8s',[['a', a 10/L], ['b', b 10/L],['c', c 10/L],['showfbd','false']])}

$\\var{qty(L,unit[0])}$ long beam $AB$ is subjected to a distributed load which

varies uniformly from $\\var{Q0}$ at $x=\\var{QA}$ to $\\var{QW}$ at $x=\\var{QB}$, and
is constant $\\var{QW}$ between $x=\\var{if(c<b,QC,QB)}$ and $x=\\var{if(c<b,QB,QC)}$.
varies uniformly from $\\var{QW}$ at $x=\\var{QB}$ to $\\var{Q0}$ at $x=\\var{QA}$.

Determine the reactions at $A$ and $B$.

", "advice": "

{geogebra_applet('xgjx2s8s',[['a', a 10/L], ['b', b 10/L],['c', c 10/L],['showfbd','true']])}

Draw a free body diagram of the beam, replacing the distributed loads with equivalent concentrated loads at the centroids of the triangle and rectangle.
Determine locations of the centroids and the 'area' under the loading curve for each part.\n
$\\begin{align}\\\\ W_R &= \\var{QWR} & x_R &= \\var{QxR} \\\\ W_T &= \\var{QWT} &x_T &= \\var{QxT}\\end{align}$
\n
Find the reactions\n
$\\begin{align}\\\\ \\Sigma M_A &= 0 \\\\W_R x_r + W_T x_T &= B L \\\\ B &= \\frac{W_R x_r + W_T x_T}{L} \\\\&= \\var{QRB} \\\\ \\\\ \\Sigma F_y &= 0 \\\\ A + B &= W_T + W_R \\\\ A &= W_T + W_R - B \\\\ &= \\var{QRA} \\end{align}$
\n
You may check your answer by finding $A$ using $\\Sigma M_B = 0$. You should get the same result either way.

", "rulesets": {}, "variables": {"a": {"name": "a", "group": "Ungrouped variables", "definition": "random(0..L)", "description": "

horizontal location of the starts of the triangular load.

could be on the left or right of point B

", "templateType": "anything"}, "b": {"name": "b", "group": "Ungrouped variables", "definition": "random(0..L)", "description": "

horizontal position of point between triangle and rectangle. l

", "templateType": "anything"}, "c": {"name": "c", "group": "Ungrouped variables", "definition": "random(0..L)", "description": "

horizontal location of the end of the rectangular load.

could be on the left or right of point B

", "templateType": "anything"}, "w": {"name": "w", "group": "Ungrouped variables", "definition": "random(50..150#10)", "description": "

Max value of loading in [force/distance]

", "templateType": "anything"}, "WT": {"name": "WT", "group": "solution", "definition": "abs(a-b) w /2", "description": "

weight of the triangular load

", "templateType": "anything"}, "WR": {"name": "WR", "group": "solution", "definition": "abs(b-c) w", "description": "

weight of the rectangular load

", "templateType": "anything"}, "WTot": {"name": "WTot", "group": "solution", "definition": "WT+WR", "description": "

Total weight of load

", "templateType": "anything"}, "xR": {"name": "xR", "group": "solution", "definition": "(b+c)/2", "description": "

location of centroid of rect

", "templateType": "anything"}, "xT": {"name": "xT", "group": "solution", "definition": "b + (a-b)/3", "description": "

Centroid of triangle

", "templateType": "anything"}, "L": {"name": "L", "group": "Ungrouped variables", "definition": "random([10,12,16,20])", "description": "

length of beam

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$A = $ [[0]] $B = $ [[1]]

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

Modify the unit portion of the student's answer by

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

2. replacing '-' with ' '

3. replacing '°' with ' deg'

to allow answers like 10 ft-lb and 30°

This fixes the student answer for two common errors.

If student_units are wrong - replace with correct units

If student_scalar has the wrong sign - replace with right sign

If student makes both errors, only one gets fixed.

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": [["question-resources/dist-load.ggb", "/srv/numbas/media/question-resources/dist-load.ggb"]]}