The maximum height that an average person can jump from a crouched start is about 60 cm. by how much does the gravitational potential energy increase for a 72 kg person in such a jump?

423.36 J

Explanation:

Change in gravitational potential energy= mgh where m is the mass of the displaced object g is the acceleration due to gravity and h is the displacement along a plane parallel to gravity vector.

From the question.m= 72kg, h=60cm=0.6m

g=9.8m/s²

Δ PE= 72kg×9.8m/s²×0.6m

=423.36 J

no. bullets are macro objects. wave nature is for light waves, extremely tiny particles. if a light particle was the size of your finger, the bullet would be the size of the universe. so basically, that huge difference in size makes the wave nature of matter insignificant.