Motion
Motion is the continuous change of position in space.
Motion is the change in position of an object or fluid with respect to a reference frame over a given time. It is mathematically described in terms of vector quantities such as displacement, velocity, and acceleration. The branch of physics describing motion without reference to its cause is kinematics, while the branch studying forces and their effect on motion is dynamics.
- field
- Physics
- key_concepts
- Displacement, velocity, acceleration, kinematics, dynamics
- branches
- Classical mechanics, relativistic mechanics, quantum mechanics
- types
- Relative motion, absolute motion (undetermined), imperceptible motion
- applications
- Objects, bodies, particles, fields, radiation, space-time, waves, quantum particles
Lore & Background
Quantum mechanics describes motion at the atomic and subatomic level, including wave–particle duality and the Heisenberg uncertainty principle, which states that the complete state of a subatomic particle, such as its location and velocity, cannot be simultaneously determined. The universe itself is expanding, as evidenced by Hubble's law, which shows all galaxies moving away from Earth.
Reader's Guide
Motion is a fundamental concept in physics, underlying the description of everything from subatomic particles to galaxies. Its study is divided into kinematics (describing motion without causes) and dynamics (studying forces and their effects). Classical mechanics, based on Newton's laws, accurately describes macroscopic objects moving at non-relativistic speeds. Relativistic mechanics extends this to high speeds and gravity, while quantum mechanics handles atomic and subatomic phenomena. The concept of motion also applies to fields, radiation, and space-time itself. The expansion of the universe represents a form of motion that does not involve physical movement but a fundamental change in the nature of spacetime. Humans are in constant motion, though many motions are imperceptible without special tools.
Did You Know?
- Everything in the universe can be considered to be in motion, as there is no absolute frame of reference.
- In quantum mechanics, the Heisenberg uncertainty principle prevents the simultaneous determination of a subatomic particle's location and velocity.
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