Computer Science I / Work, Energy, and Power
Practice question · True or false

A ball dropped from a given height arrives at the ground with a speed that does not depend on its mass.

Hints
  1. Set the potential energy equal to the kinetic energy.
  2. The mass appears on both sides.
Show the answer

True

Why

True. mgh=12mv2mgh = \tfrac12 mv^{2} gives v=2ghv = \sqrt{2gh}, the mass cancels. That is Galileo's result, and it holds only while air resistance is negligible: a feather and a hammer fall together on the Moon and visibly do not on Earth, because drag depends on shape and area rather than mass.

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