// Numbas version: finer_feedback_settings
{"name": "Dot and cross product combinations", "extensions": [], "custom_part_types": [], "resources": [], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"parts": [{"displayType": "radiogroup", "layout": {"type": "all", "expression": ""}, "choices": ["$\\boldsymbol{(v\\cdot w)\\cdot u}$", "$\\boldsymbol{(v\\cdot w)u}$", "$\\boldsymbol{(v\\cdot w)\\times u}$", "$\\boldsymbol{(v\\times w)\\times u}$", "<p>$\\boldsymbol{(v\\times w)\\cdot u}$</p>"], "variableReplacementStrategy": "originalfirst", "matrix": [[0, 0, 0.4], [0, 0.4, 0], [0, 0, 0.4], [0, 0.4, 0], [0.4, 0, 0]], "shuffleChoices": true, "type": "m_n_x", "maxAnswers": 0, "marks": 0, "warningType": "none", "scripts": {}, "minMarks": 0, "minAnswers": 0, "maxMarks": 0, "shuffleAnswers": true, "showCorrectAnswer": true, "variableReplacements": [], "answers": ["<p>Scalar</p>", "<p>Vector</p>", "<p>Undefined</p>"]}], "variables": {}, "ungrouped_variables": [], "rulesets": {"std": ["all", "fractionNumbers", "!collectNumbers", "!noLeadingMinus"]}, "name": "Dot and cross product combinations", "functions": {}, "variable_groups": [], "showQuestionGroupNames": false, "variablesTest": {"condition": "", "maxRuns": 100}, "statement": "<p>Given the vectors $\\boldsymbol{v}$, $\\boldsymbol{w}$, $\\boldsymbol{u}$ in $\\mathbb{R}^3$, state whether the following quantities are scalars (real numbers), vectors (elements of $\\mathbb{R}^3$) or undefined.</p>\n<p>In this question, the&nbsp;symbol $\\cdot$ denotes the inner product and $\\times$ always denotes the cross product.</p>", "tags": ["checked2015", "cross product", "dot product", "inner product", "MAS1602", "mas1602", "scalar product", "scalars", "unused", "vector", "Vector", "vector product", "vectors"], "question_groups": [{"pickingStrategy": "all-ordered", "questions": [], "name": "", "pickQuestions": 0}], "preamble": {"css": "", "js": ""}, "type": "question", "metadata": {"notes": "\n        \t\t<p><strong>15/07/2012:</strong></p>\n        \t\t<p>Added tags.</p>\n        \t\t<p><strong>16/07/2012:</strong></p>\n        \t\t<p><strong>Added tags.<br /></strong></p>\n        \t\t<p><strong>&nbsp;</strong></p>\n        \t\t<p><strong>&nbsp;</strong></p>\n        \t\t", "licence": "Creative Commons Attribution 4.0 International", "description": "<p>Determine if various combinations of vectors are defined or not.</p>"}, "advice": "<p>1. $\\boldsymbol{(v\\cdot w)\\cdot u}$ is <b>undefined</b> as $\\boldsymbol{v\\cdot w}$ is a scalar and we cannot take the inner product of a scalar with the vector $\\boldsymbol{u}$.</p>\n<p>2. $\\boldsymbol{(v\\cdot w) u}$ is a <b>vector</b> and is a scalar multiple of $\\boldsymbol{u}$ as $\\boldsymbol{v \\cdot w}$ is a scalar.</p>\n<p>3. $\\boldsymbol{(v \\cdot w)\\times u}$ is <b>undefined</b> as $\\boldsymbol{v\\cdot w}$ is a scalar and the cross product is only defined between vectors.</p>\n<p>4. $\\boldsymbol{(v\\times w)\\times u}$ is a <b>vector</b> as $\\boldsymbol{v \\times w}$ and $\\boldsymbol{u}$ are vectors and the cross product between vectors produces a vector.</p>\n<p>5. $\\boldsymbol{(v\\times w)\\cdot u}$ is a <b>scalar</b> as $\\boldsymbol{v \\times w}$ and $\\boldsymbol{u}$ are vectors and the inner or dot product is between vectors and produces a scalar.</p>", "contributors": [{"name": "Newcastle University Mathematics and Statistics", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/697/"}]}]}], "contributors": [{"name": "Newcastle University Mathematics and Statistics", "profile_url": "https://numbas.mathcentre.ac.uk/accounts/profile/697/"}]}