// Numbas version: finer_feedback_settings {"name": "Haifa's new exponential equation to solve for radioactivity", "extensions": [], "custom_part_types": [], "resources": [["question-resources/pict_1.png", "pict_1.png"], ["question-resources/pict_1_ITOj7zB.png", "pict_1_ITOj7zB.png"], ["question-resources/pict_1_uVwY3Xh.png", "pict_1_uVwY3Xh.png"], ["question-resources/pict_1_KKrpSKi.png", "pict_1_KKrpSKi.png"], ["question-resources/pict_1_H05SCRT.png", "pict_1_H05SCRT.png"]], "navigation": {"allowregen": true, "showfrontpage": false, "preventleave": false, "typeendtoleave": false}, "question_groups": [{"pickingStrategy": "all-ordered", "questions": [{"variablesTest": {"condition": "", "maxRuns": "100"}, "metadata": {"licence": "Creative Commons Attribution 4.0 International", "description": "
Solve an exponential equation for radioactivity
"}, "statement": "The radioactivity of fallout t days after a nuclear explosion is modeled by
If the radioactivity is found to be \\(1/\\var{2^a}\\) of the original amount after \\(\\var{t}\\) days, find the value of \\(k\\)
", "rulesets": {}, "advice": "\\(\\var{k}=\\var{a}e^{\\var{m}x+{\\var{c}}}\\)
\n\\(\\frac{\\var{k}}{\\var{a}}=e^{\\var{m}x+\\var{c}}\\)
\n\\(ln\\left(\\frac{\\var{k}}{\\var{a}}\\right)=\\var{m}x+\\var{c}\\)
\n\\(ln\\left(\\frac{\\var{k}}{\\var{a}}\\right)-\\var{c}=\\var{m}x\\)
\n\\(\\frac{ln\\left(\\frac{\\var{k}}{\\var{a}}\\right)-\\var{c}}{\\var{m}}=x\\)
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\n\\(k = \\) [[0]]
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