Last weekend was the OBDA Select Stage Band concert in Seto Hall. I played the Bari Sax in this band and as usual got tired while caring my saxophone all around campus, band room to Seto Hall and back. My saxophone in its case is pretty heavy, but sadly, as I have learned from physics I do not do any work while I carry it, no matter how heavy it is, how long I carry it, or how tired I get.
Work is force x distance but since when I carry my saxophone I am applying force in an upward direction while I am walking forward, the force and distance vectors are perpendicular and so no work is being done.
I do however do a small amount of work while moving my saxophone and interestingly enough, the more times I stop and rest, the more work I do. Why? Because when I pick-up my saxophone I am in fact doing work, even though I am not while walking. When I lift my saxophone I am applying an upward force of the mass times the acceleration of my saxophone, and because it is also moving a distance in the same direction (upwards) work is being done as calculated by equation Work=force times displacement.
Also, when I am standing still with my saxophone it has potential energy of mass times g times the height at which I am holding the case.
(Sorry I do not have my actual saxophone to take a picture of, but this painting gives the general idea)
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