Final answer:
Objects affected by gravity and friction possess mechanical energy, which consists of potential and kinetic energy. Specifically, the restoring force in a splashing liquid is mechanical energy, the energy of snow on a roof is potential energy, and the force holding an atom together is electric.
Step-by-step explanation:
Objects primarily affected by the force of gravity and frictional forces posses mechanical energy. Mechanical energy is the sum of an object's potential energy, which is the energy due to its position in a gravitational field, and its kinetic energy, which is the energy due to its motion.
Whether an object is in motion or positioned at a height where it could fall, the mechanical energy encompasses both these states. For example, when a foot of snow is on a steep roof, it has potential energy, and the energy removed from a system by a non-conservative damping force, like friction, is typically in the form of thermal energy.
Let's apply this understanding to the given scenarios:
- The splashing of a liquid resembles an oscillation, and the restoring force in this scenario will be due to mechanical energy.
- The energy stored in a foot of snow on a steep roof is potential energy.
- The force responsible for holding an atom together is electric.
Focusing on the splashing of a liquid, the conversion between potential and kinetic energy within the fluid's movement creates an oscillating system that is best described by mechanical energy. This reflects the Law of Conservation of Mechanical Energy, which states that in a closed system without external dissipative forces, the mechanical energy remains constant.