JAMB Physics 2019 Paper

Concept:A freely falling body obeys the law of conservation of mechanical energy.Explanation:• As the body falls, its potential energy $\text{PE}$ decreases while its kinetic energy $\text{KE}$ increases.• At any point during the fall, the total energy is the sum of both forms:$$E = \text{PE} + \text{KE}.$$• Since no external work is done on the system, this sum remains constant throughout the motion.• Statement I is false because the body possesses both kinetic and potential energy at most points, not entirely kinetic energy.• Statement II is false because the ratio $\frac{\text{PE}}{\text{KE}}$ changes continuously as the body falls.• Statement III is true because the sum of potential and kinetic energy is always constant.Answer:C. III only