Final answer:
A person standing on the ground has a potential energy of 0 J relative to the ground. If they jump, the potential energy at 1m above the ground is calculated as mgh J. Once they land, the potential energy is again 0 J.
Step-by-step explanation:
The potential energy of a person standing can be calculated using the formula G.P.E. = mgh, where m is the mass of the person, g is the acceleration due to gravity (approximately 9.8 m/s²), and h is the height above the ground. Since the person is standing on the ground, their height above the ground (h) is 0 meters. Therefore, the potential energy relative to the ground is calculated as 0 J because when h=0, mgh also equals 0, no matter the mass of the person.
If the person jumps and is 1m from the ground, the potential energy can be found using the same formula, however, this time h=1. So the potential energy is mgh J where m is the mass of the boy and g is the acceleration due to gravity. When the person lands on the ground, the height becomes 0 again, and thus, the potential energy at that point is also 0 J.