I’ve been grading lab reports in two different classes, and I’ve been struck once again by the way that students attach mystical properties to anything with a digital readout. The uncertainty used in calculations is invariably put down as half of whatever the least significant digit displayed was, even in cases where the readout visibly fluctuated during the measurement.<\/p>\n
Even better, any experiment involving length measurements will inevitably produce lab reports suggesting that the uncertainty could’ve been improved if they had had a caliper with a digital readout, rather than a vernier caliper. <\/p>\n
I think that the next time I do my usual introduction to uncertainty analysis, I’m going to borrow the digital-readout caliper from the shop, and have everybody in the class measure the length of some rough block of metal. Maybe seeing the variation in the results will drive home that digital metering only creates the illusion<\/strong> of absolute precision…<\/p>\n","protected":false},"excerpt":{"rendered":" I’ve been grading lab reports in two different classes, and I’ve been struck once again by the way that students attach mystical properties to anything with a digital readout. The uncertainty used in calculations is invariably put down as half of whatever the least significant digit displayed was, even in cases where the readout visibly… Continue reading Digital Is Not Infallible<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"1","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[],"class_list":["post-2582","post","type-post","status-publish","format-standard","hentry","category-physics","entry"],"_links":{"self":[{"href":"http:\/\/chadorzel.com\/principles\/wp-json\/wp\/v2\/posts\/2582","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/chadorzel.com\/principles\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/chadorzel.com\/principles\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/chadorzel.com\/principles\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"http:\/\/chadorzel.com\/principles\/wp-json\/wp\/v2\/comments?post=2582"}],"version-history":[{"count":0,"href":"http:\/\/chadorzel.com\/principles\/wp-json\/wp\/v2\/posts\/2582\/revisions"}],"wp:attachment":[{"href":"http:\/\/chadorzel.com\/principles\/wp-json\/wp\/v2\/media?parent=2582"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/chadorzel.com\/principles\/wp-json\/wp\/v2\/categories?post=2582"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/chadorzel.com\/principles\/wp-json\/wp\/v2\/tags?post=2582"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}