Vijay Shankar Sharma
Textbook physics terms. Not a BFUT reinterpretation. 371 terms. Textbook meanings only.
16 terms. Page 1 of 1.
thermo · intro
An equation of state that relates the pressure, volume, temperature, and amount of an idealized gas, combining Boyle's law, Charles's law, and Avogadro's principle into a single expression. It assumes gas particles have negligible volume and no interactions except during perfectly elastic collisions. While no real gas behaves perfectly ideally, the ideal gas law provides an excellent approximation for many gases under normal temperature and pressure conditions.
mechanics · intro
The change in an object's momentum produced by a force acting over a period of time, calculated as the force multiplied by the time interval during which it acts, or equivalently as the area under a force-versus-time graph. Impulse explains why extending the time of a collision, such as with airbags or padded flooring, reduces the peak force experienced, since the same change in momentum is spread over a longer time.
mechanics · intro
A flat surface set at an angle to the horizontal, used as a simple machine to reduce the force needed to raise an object to a given height at the cost of moving it a longer distance. Ramps, wedges, and screws are all variations on the inclined plane principle. Analyzing motion on an inclined plane requires resolving gravity into components parallel and perpendicular to the sloped surface.
mechanics · intro
A collision between two or more objects in which total momentum is conserved but total kinetic energy is not, with some kinetic energy converted into other forms such as heat, sound, or permanent deformation. A perfectly inelastic collision is the extreme case where the colliding objects stick together and move with a common velocity afterward. Most real-world collisions, from car crashes to a ball of clay hitting the floor, are inelastic to some degree.
mechanics · intro
The tendency of an object to resist changes in its state of motion, whether at rest or moving at constant velocity, as described by Newton's first law of motion. An object's inertia is directly related to its mass; more massive objects require a larger force to achieve the same acceleration. Inertia explains why passengers in a car lurch forward when the car suddenly brakes, since their bodies tend to continue moving at the original speed.
mechanics · intermediate
A frame of reference in which an object with no net force acting on it moves at constant velocity, neither accelerating nor decelerating, consistent with Newton's first law. A frame that is itself accelerating or rotating, such as a spinning carousel, is a non-inertial frame, in which apparent forces like the Coriolis effect must be introduced to explain motion. Special relativity is built around the physics observed in inertial frames.
cosmology · intermediate
Also called: cosmic inflation
A theorized period of extremely rapid, exponential expansion of space that is proposed to have occurred a tiny fraction of a second into the universe's earliest history, before the standard hot expansion phase, within the framework of Lambda-CDM cosmology. Inflation was proposed to explain several observed features of the universe, including its large-scale flatness, uniform temperature, and the specific pattern of tiny density fluctuations that later seeded the formation of galaxies.
em · intro
Electromagnetic radiation with wavelengths longer than visible light but shorter than microwaves, commonly associated with heat, since most objects at room temperature emit strongly in the infrared. Infrared cameras detect this radiation to create thermal images even in complete darkness, and infrared light is used in remote controls, fiber-optic communication, and astronomical observations of dust-obscured regions of space.
em · intro
A material that strongly resists the flow of electric charge, or in a different context, heat, because it has very few charge carriers free to move within it. Materials like rubber, glass, and most plastics are good electrical insulators, used to coat wires and prevent unwanted current flow or electric shock. Thermal insulators, such as foam or wool, slow the transfer of heat by conduction.
cosmology · intermediate
Also called: ISW effect
A secondary effect that produces small additional temperature fluctuations in the cosmic microwave background, caused by photons gaining or losing energy as they pass through evolving gravitational potential wells, such as large cosmic voids or superclusters, during the universe's dark-energy-dominated expansion phase. Detecting this effect provides independent evidence for the presence of dark energy, since the effect would not occur in a universe where cosmic structures remained static over time.
waves · intro
The phenomenon that occurs when two or more waves overlap in the same region of space, combining according to the principle of superposition to produce a resulting wave that can be larger, smaller, or equal to the individual waves, depending on their relative phase. Constructive interference occurs when waves reinforce each other, while destructive interference occurs when they partially or fully cancel. Interference is a defining signature of wave behavior.
thermo · intermediate
The total energy contained within a system due to the microscopic kinetic and potential energy of its constituent particles, including molecular motion, vibrations, and intermolecular forces, but excluding the system's overall kinetic and potential energy as a whole object. Internal energy changes when heat is added or removed, or when work is done on or by the system, as described by the first law of thermodynamics.
mechanics · intro
A mathematical relationship in which a physical quantity's intensity or strength decreases in proportion to the square of the distance from its source. Gravity, electric fields, and the intensity of light and sound all follow inverse-square laws in idealized point-source situations, meaning doubling the distance from a source reduces the effect to one quarter of its original strength. This pattern arises naturally because the influence spreads out over the surface of an expanding sphere.
quantum · intro
An atom or molecule that has gained or lost one or more electrons, giving it a net positive or negative electric charge. Atoms that lose electrons become positively charged cations, while atoms that gain electrons become negatively charged anions. Ions are essential to chemistry, biology, and physics, playing roles ranging from nerve signal transmission in the body to the behavior of plasmas in stars and fluorescent lights.
quantum · intermediate
The minimum energy required to remove an electron from an atom or molecule in its gaseous state, converting it into a positively charged ion. Ionization energy generally increases across a row of the periodic table and decreases down a column, reflecting how tightly outer electrons are bound to the nucleus. High-energy radiation capable of ionizing atoms, such as ultraviolet light and X-rays, is called ionizing radiation and can damage biological tissue.
nuclear · intro
One of two or more forms of the same chemical element whose atoms have the same number of protons but different numbers of neutrons, giving them different atomic masses while retaining nearly identical chemical properties. Some isotopes are stable indefinitely, while others are radioactive and decay over time at a characteristic rate. Carbon-12 and carbon-14 are isotopes of carbon, differing only in their number of neutrons.