The correct response is:
Mass is eliminated when equating gravitational potential energy with kinetic energy.
In the context of conservation of mechanical energy, the total mechanical energy (the sum of potential and kinetic energy) remains constant as long as only conservative forces (like gravity) are doing work. The gravitational potential energy (PE) is given by the equation \( PE = mgh \), and the kinetic energy (KE) is given by \( KE = \frac{1}{2}mv^2 \).
When setting the initial potential energy equal to the final kinetic energy at the moment just before hitting the ground, we have:
\[ mgh = \frac{1}{2}mv^2 \]
Here, the mass \( m \) can be cancelled out from both sides of the equation (as long as \( m \) is not zero), leading to:
\[ gh = \frac{1}{2}v^2 \]
This shows that the relationship between height, gravitational force, and velocity is independent of mass, demonstrating that the conservation of mechanical energy does not depend on the mass of the object.