Today’s a lab day in my main class for the term, with a fairly involved experiment to measure the charge-to-mass ratio of the electron. This is going to be all kinds of fun, because 1) I can’t get into the room to set anything up until an hour before the start of class, and 2) SteelyKid is home sick, which means I can’t go in to pull stuff together until about an hour before the start of class. Whee!<\/p>\n
Today’s a day to (attempt to) accentuate the positive, though, so let’s use this as a jumping-off point for a more upbeat topic, namely:<\/p>\n
\nWhat’s the best lab you ever did in a lab science class?<\/p>\n<\/blockquote>\n
This could be from any science– physics of course, but biology, chemistry, and geology have their moments, too– and “best” is totally subjective. It could be the lab that was the most fun to do, or the one that made the most interesting or precise measurement, or the one that failed in the most spectacular manner. Leave your favorite in the comments.<\/p>\n
My personal choice is an easy one: the “Ballistic Pendulum” lab we did when I was an undergrad.<\/p>\n
<\/p>\n
The “Ballistic Pendulum” is a technique for measuring the speed of a fast-moving projectile by firing it into a much heavier mass that is suspended to act as a pendulum. From the fact that momentum is conserved in the collision, and energy is conserved after the collision, you can use the maximum height reached by the pendulum to determine the initial speed of the projectile.<\/p>\n
We do this in our intro mechanics classes using a PASCO set-up with a spring-loaded launcher that fires a metal ball into a metal-and-plastic pendulum, and records the angle. It’s an okay lab, but nothing too brilliant.<\/p>\n
Back in the stone age when I was an undergrad, though, we did this with a .22 rifle and a heavy wooden pendulum. Now, that<\/em> was an impressive lab… I particularly enjoyed the year when I TA’ed the lab for the pre-med class. I told them at the start of class that we would be firing a rifle in the lab, and offered them earplugs. They all laughed at me. So I set myself up in a place where I could see the whole room when the first group fired the gun, and got to watch the center of mass of the room go up by about 10cm when they heard the gunshot. Good times, good times…<\/p>\n
Sadly, you’d never be able to do that lab today without a SWAT team busting in and screwing up the error analysis. But it did make the point very impressively.<\/p>\n
So, what’s your<\/em> favorite lab class story?<\/p>\n
(This is not-quite a payoff to Paul A., who asked for more True Lab Stories with his DonorsChoose donation. The generation of a real Lab Story has been delayed by SteelyKid’s illness, but I’ll try to come up with something.)<\/p>\n","protected":false},"excerpt":{"rendered":"
Today’s a lab day in my main class for the term, with a fairly involved experiment to measure the charge-to-mass ratio of the electron. This is going to be all kinds of fun, because 1) I can’t get into the room to set anything up until an hour before the start of class, and 2)… Continue reading Best. Lab. EVER.<\/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":[8,13,19,7,11],"tags":[],"class_list":["post-5159","post","type-post","status-publish","format-standard","hentry","category-academia","category-education","category-experiment","category-physics","category-science","entry"],"_links":{"self":[{"href":"http:\/\/chadorzel.com\/principles\/wp-json\/wp\/v2\/posts\/5159","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=5159"}],"version-history":[{"count":0,"href":"http:\/\/chadorzel.com\/principles\/wp-json\/wp\/v2\/posts\/5159\/revisions"}],"wp:attachment":[{"href":"http:\/\/chadorzel.com\/principles\/wp-json\/wp\/v2\/media?parent=5159"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/chadorzel.com\/principles\/wp-json\/wp\/v2\/categories?post=5159"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/chadorzel.com\/principles\/wp-json\/wp\/v2\/tags?post=5159"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}