A physical body is an enduring object that maintains a specific spatial trajectory and orientation over a period, existing within the realm of physical space as studied by physics.
In more detail, a physical body can be understood through these characteristics:
- Enduring Object: It's not fleeting; it exists for a duration. It's not a momentary event, but something that persists through time.
- Spatial Trajectory: The body occupies space and moves (or remains stationary) along a specific path. This trajectory is key to understanding its motion and position.
- Orientation: How the body is positioned in space matters. Its orientation affects how it interacts with its environment. Think of a spinning top vs. a lying top.
- Physical Space: It exists within the universe governed by physical laws, subject to gravity, electromagnetism, and other fundamental forces. It is directly observable and measurable, at least in principle.
- Studied by Physics: The behavior and properties of a physical body fall under the domain of physics. This includes its mass, volume, density, velocity, and interaction with other physical bodies.
Examples of physical bodies include:
- A rock
- A planet
- A car
- A human being
- An atom
Essentially, anything that occupies space, has mass, and can be observed and studied according to the laws of physics can be considered a physical body.
