'(<a href="http://www.j-archive.com/media/2010-06-16_DJ_18.wmv">Kelly of the Clue Crew dissects and demonstrates a doorknob.</a>)  A doorknob acts as a force multiplier, with a larger knob turning a smaller attached shaft--an example of this simple machine'
wheel and axle
SCIENCE CLASS: A doorknob acts as a force multiplier, with a larger knob turning a smaller attached shaft--an example of this simple machine
A doorknob acts as a force multiplier, with a larger knob turning a smaller attached shaft--an example of this simple machine
A doorknob acts as a force multiplier, with a larger knob turning a smaller attached shaft--an example of this simple machine
SCIENCE CLASS
wheel and axle
SCIENCE CLASS