Too often a science unit on simple machines consists of a discussion of ideal mechanical advantage (I.M.A.) and actual mechanical advantage (A.M.A.) in pulley systems and inclined planes, without really emphasizing the role of friction.
Iowa Science Teachers' Journal
© Copyright 1964 by the Iowa Academy of Science
Snoble, Joseph J.
"Determining the Force of Friction in a Simple Machine,"
Iowa Science Teachers Journal: Vol. 1
, Article 4.
Available at: https://scholarworks.uni.edu/istj/vol1/iss4/4