Measurement and Uncertainty Objectives After completing this section, students will be able to: 1. Explain what is a standard measurement is and why it is used, 2. compare and contrast accuracy and precision, 3. identify and compare and contrast length, volume, mass and time, 4. accurately measure length, volume, mass and time, using the proper device, 5. compute the density of an object, 6. tabulate and compute the average of a series of measurements. Making observations requires the use of measurements. Whether it is counting the number of occurrences in a sample population, the speed at which a bullet leaves a gun barrel, or the number of molecules of a given compound which are necessary to complete a given reaction, observation has at its core taking accurate measurements. A quick, visual lesson on units. Here is the NIST reference on Constants, Units and Uncertainty. Here is a good reference on accuracy verses precision. Here is an example in use, calculating rifle precision. Inherent in the use of measurements is the ability to convert between various units of measurements. This site is very useful in finding the conversion factor. So is this one. And here is a page of links to hundreds more! Scaling is an important concept. Here is an outdoor activity that demonstrates the scale of the solar system. The basketball court width measurement exercise. And one to measure the football field. The exercise for determining the density of a liquid. The lab on weighing paper clips. The exercise for determining the density of pennies. And the worksheet. Density Applet http://www.explorescience.com/activities/Activity_page.cfm?ActivityID=29 Virtual School http://www.accessed.qld.edu.au/home/mirror/contents/topic01.htm
|
Send mail to
dyrwolf@embarqmail.com with
questions or comments about this web site.
|