A stone is launched upaward into the air. In addition to the force of gravity, the stone is subject to frictional forces fue to air resistance. Is the time to reach the top of its flight equal to, smaller or larger than the time to come back to its original position?
2 answers
I do believe that the answer is equal to.
The stone lands with a velocity less than that at which it was thrown, because of frictional energy loss. Therefore the average velocity (which decreases from Vinitial to 0 during ascent) is larger than than the average velocity during descent (which increases from 0 to Vfinal). Since the distances up and down are the same, more time is spent coming down, at the lower average velocity.
1 answer