Estimate how much initial velocity you had. Potential energy increases, and kinetic energy decreases. Potential energy decreases, and kinetic energy is constant. Potential energy decreases, and kinetic energy is constant. Potential energy is constant, and kinetic energy increases.
Potential energy is constant, and kinetic energy is constant.
An oxygen molecule of mass M is sitting at rest minding its own business. Suddenly, a cosmic ray photon passes by and adds an energy D to the molecule. The molecule sits and wiggles for a while, and the breaks up into two equal mass oxygen atoms traveling in opposite directions. Suppose you throw your physics book out of your window after a long night of studying. You throw it straight down at the ground with velocity v. Your study partner thinks this is a great idea, and he throws his book out the window but up at an angle with a velocity v, because he figures it will make a bigger mess when it lands.