A 75kg boater tosses a 5kg anchor horizontally, straight forward across the
bow of his 125kg boat at 2m/s relative to the water. a) Neglecting any
horizontal force applied to the boat by the water, calculate the boat's
backward speed across the water just as the anchor leaves the boater's hand.
(The boat is initially at rest on the water.) b) At least how much work
must the boater have done to throw the anchor in this way?
But all of the PHYS-L debate about proper usage of work and energy
terminology that I have followed has caused me to worry (possibly more than
I should) about items like part b of this problem. Would some object to
this sort of question? (The expected response is that the work should equal
the total KE aquired by the boat, boater, and anchor.)
_______________________________________
Fred Lemmerhirt
Waubonsee Community College
Sugar Grove, Illinois
<mailto: flemmerhirt@mail.wcc.cc.il.us> http://chat.wcc.cc.il.us/~flemmerh/physics.html
This posting is the position of the writer, not that of SUNY-BSC, NAU or the AAPT.