Final answer:
The mechanical energy of an object equals its kinetic energy plus its potential energy, represented as KE + PE = constant.
Step-by-step explanation:
This means that the correct answer is B. It is important to understand that mechanical energy refers to the sum of kinetic energy (KE), which is energy due to motion, and potential energy (PE), which is energy due to position.
Gravitational potential energy is a form of potential energy that an object possesses due to its position in a gravitational field. The concept of conservation of mechanical energy states that in a closed system with no external dissipative forces, the total mechanical energy remains constant. This can be expressed in equation form as KE + PE = constant.
In cases involving charged particles, a loss of PE results in an increase in KE, reflecting the conservation of energy within a system. Hence, the mechanical energy is a scalar quantity often measured in joules (J).