2007-01-09 09:07:02 · 4 answers · asked by lincolngomes301 2 in Science & Mathematics ➔ Physics
The previous answer is not, strictly speaking, correct.
While it would take NO WORK to keep something moving on a frictionless surface, it would take a very definitely prescribed amount of work to get it up to the velocity 'v' with which it's sliding, in the first place. If its mass is 'm,' that amount of work would be:
(1/2) m v^2,
only minuscule if 'v' is minuscule. If 'v' is a good, large macroscopic velocity (or speed), that needed work could still be fairly significant.
Live long and prosper.
2007-01-09 09:16:32 · answer #1 · answered by Dr Spock 6 · 1⤊ 0⤋
If the surface is truly frictionless and in vacuum, the amount of work required for perpetual motion would be miniscule at the outset and none to keep it moving.
2007-01-09 17:11:41 · answer #2 · answered by Shibi 6 · 0⤊ 0⤋
Yep, none to keep it moving as long as it's in a vacuum. Newton's first law: "Every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it."
2007-01-09 17:18:38 · answer #3 · answered by JimGeek 4 · 0⤊ 0⤋
None.
2007-01-09 17:21:39 · answer #4 · answered by Anonymous · 0⤊ 0⤋