. A runner jumps over a hurdle. Neglecting friction, the potential energy of the runner at
the highest point compared to his kinetic energy at the lowest point is
C. Greater
Why greater?
To compare the potential energy of the runner at the highest point to his kinetic energy at the lowest point, we need to understand the relationship between potential energy and kinetic energy.
Potential energy (PE) is the energy possessed by an object due to its position or condition. In this case, the runner has potential energy at the highest point, which is the point when the runner is about to jump over the hurdle.
Kinetic energy (KE), on the other hand, is the energy possessed by an object due to its motion. The runner will have kinetic energy at the lowest point, which is the point when the runner is just about to touch the ground after jumping over the hurdle.
To determine the relationship between the potential energy and kinetic energy, we can use the principle of conservation of energy. According to this principle, the total energy of a system remains constant, and it can only be converted from one form to another.
In this case, as the runner jumps over the hurdle, his potential energy at the highest point is gradually converted into kinetic energy as he falls to the ground. At the lowest point, when the runner is about to touch the ground, all the potential energy has been converted into kinetic energy.
Therefore, the potential energy at the highest point is equal to the kinetic energy at the lowest point. Both energies are the same because they are part of the total energy of the runner, which remains constant.
In conclusion, neglecting friction, the potential energy of the runner at the highest point is equal to the kinetic energy of the runner at the lowest point.