Unit Four Review

Below is a key for the review sheet.

You might also consider trying these questions from the Red Textbook
p169-173:  17, 18, 26, 32, 38, 49, 50, 52, 54
p133:  14-16
p146: 30, 34

Review Answers 2013 More Forces Unit

Gecko Friction

In some classes I mentioned that Geckos use frictional force to climb surfaces in a surprising way - not through surface irregularities and tiny hooks, but through electrostatic attractions.

Here is a link to a NOVA episode about it.  The gecko section starts at about the 11 minute mark.

http://www.pbs.org/wgbh/nova/tech/making-stuff.html#making-stuff-smarter