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Standard physics glossary
Textbook physics terms. Not a BFUT reinterpretation. 371 terms. Textbook meanings only.
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7 terms. Page 1 of 1.
em · intro
Ohm's Law
A fundamental relationship in electrical circuits stating that the current flowing through a conductor between two points is directly proportional to the voltage across those two points, with resistance as the constant of proportionality, commonly written as voltage equals current multiplied by resistance. Named after German physicist Georg Ohm, it applies well to many conductors and resistors under normal conditions, though some materials and components deviate from this simple linear relationship.
cosmology · intermediate
Omega Lambda
A dimensionless cosmological parameter representing the ratio of the energy density associated with the cosmological constant, or dark energy, to the critical density needed for a spatially flat universe. Current measurements within the standard Lambda-CDM model place omega lambda at approximately 0.7, making dark energy the dominant component of the universe's total energy content and the primary driver of its accelerating expansion.
cosmology · intermediate
Omega Matter
A dimensionless cosmological parameter representing the ratio of the actual average matter density in the universe, including both ordinary and dark matter, to the critical density needed for a spatially flat universe. Current measurements within the standard Lambda-CDM model place omega matter at approximately 0.3, meaning matter accounts for about 30 percent of the universe's total energy budget, with dark energy making up most of the remainder.
astro · intro
Orbit
The curved path an object follows around another object due to gravitational attraction, such as a planet orbiting the Sun or a satellite orbiting Earth. Stable orbits are typically elliptical, with circular orbits representing a special case, and are governed by the balance between an object's forward velocity and the inward pull of gravity. Kepler's laws and Newton's law of gravitation together provide the mathematical framework for describing and predicting orbital motion.
astro · intro
Orbital Period
The time it takes for an object to complete one full orbit around another object, such as the time for a planet to orbit its star or a moon to orbit its planet. According to Kepler's third law, the square of a planet's orbital period is proportional to the cube of its average distance from the Sun, meaning planets farther out take proportionally much longer to complete an orbit.
astro · intermediate
Orbital Velocity
The speed an object must maintain to stay in a stable orbit around a massive body, resulting from the balance between the object's tendency to move in a straight line and the inward pull of gravity constantly curving its path. Orbital velocity depends on the mass of the central body and the distance from it; objects in lower orbits must travel faster to avoid falling, while those in higher orbits move more slowly.
waves · intro
Oscillation
A repetitive back-and-forth or up-and-down variation of a physical quantity around some equilibrium value, occurring in systems ranging from a swinging pendulum and a vibrating guitar string to alternating electric current and quantum mechanical wavefunctions. Simple harmonic motion is the most basic and mathematically tractable form of oscillation, in which the restoring force is directly proportional to the displacement from equilibrium.
