Inglês para Física: Vocabulário Essencial

"inertia"

The tendency of an object to resist changes in its state of motion.

"The spacecraft maintained its trajectory through inertia once the engines cut off."

"momentum"

The product of an object's mass and velocity; a measure of motion quantity.

"Conservation of momentum explains why the cue ball slows down after striking another billiard ball."

"torque"

A rotational force that causes or changes angular motion around an axis.

"The wrench applies torque to the bolt, rotating it clockwise."

"friction"

A force that opposes the relative motion between two surfaces in contact.

"Without friction, the car tyres would not grip the road surface."

"centripetal acceleration"

The inward acceleration experienced by an object moving in a circular path.

"Centripetal acceleration keeps the satellite in its circular orbit around Earth."

"elastic collision"

A collision in which both momentum and kinetic energy are conserved.

"The physicists modelled the gas molecules as undergoing elastic collisions."

"free body diagram"

A visual representation showing all forces acting on an isolated object.

"Draw a free body diagram to identify every force before solving the problem."

"terminal velocity"

The constant speed reached when drag force equals gravitational force on a falling object.

"A skydiver reaches terminal velocity when air resistance balances the pull of gravity."

"entropy"

A measure of disorder or randomness in a thermodynamic system.

"The second law of thermodynamics states that entropy in an isolated system always increases."

"heat capacity"

The amount of heat energy required to raise the temperature of a substance by one degree.

"Water has a high heat capacity, which is why oceans moderate coastal climates."

"adiabatic process"

A thermodynamic process in which no heat is exchanged with the surroundings.

"The rapid compression of gas in a diesel engine is approximately adiabatic."

"Carnot efficiency"

The maximum theoretical efficiency of a heat engine operating between two temperatures.

"No real engine can exceed the Carnot efficiency defined by its operating temperatures."

"phase transition"

A change of matter from one state (solid, liquid, gas) to another at a specific temperature.

"The phase transition from ice to water occurs at 0 °C under standard atmospheric pressure."

"thermal equilibrium"

The state in which two bodies in contact no longer exchange heat because they are at the same temperature.

"After an hour, the metal rod reached thermal equilibrium with the surrounding air."

"latent heat"

The heat absorbed or released during a phase transition without a change in temperature.

"Steam releases latent heat when it condenses back into liquid water."

"specific heat"

The amount of heat per unit mass required to raise temperature by one degree Celsius.

"Aluminium has a lower specific heat than water, so it heats up more quickly."

"electric flux"

The measure of the electric field passing through a given surface area.

"Gauss's law relates the electric flux through a closed surface to the enclosed charge."

"magnetic permeability"

A material's ability to support the formation of a magnetic field within itself.

"Iron has high magnetic permeability, which is why it is used in transformer cores."

"electromagnetic induction"

The generation of an electric current by a changing magnetic field.

"Electromagnetic induction is the principle behind electric generators and dynamos."

"capacitance"

The ability of a component to store electric charge per unit of voltage.

"The capacitor's capacitance determines how quickly it can charge and discharge."

"impedance"

The total opposition to current flow in an AC circuit, combining resistance and reactance.

"The speaker's impedance must match the amplifier's output for optimal power transfer."

"Lorentz force"

The combined electric and magnetic force acting on a charged particle in motion.

"The Lorentz force causes electrons to curve as they enter a magnetic field."

"Maxwell's equations"

The four fundamental equations that describe how electric and magnetic fields behave and interact.

"Maxwell's equations predict that light is an electromagnetic wave."

"dielectric constant"

A measure of a material's ability to reduce the electric field and store electrical energy.

"The dielectric constant of the insulating material determines the capacitor's energy storage."

"wave function"

A mathematical description of the quantum state of a particle, encoding probabilities of measurable outcomes.

"The wave function collapses to a definite value when a measurement is made on the particle."

"superposition"

The principle that a quantum system can exist in multiple states simultaneously until measured.

"Schrödinger's famous thought experiment illustrates the concept of superposition."

"quantum entanglement"

A phenomenon in which two particles remain correlated so that measuring one instantly affects the other, regardless of distance.

"Researchers used quantum entanglement to transmit information in an experimental teleportation protocol."

"uncertainty principle"

The fundamental limit on the precision with which position and momentum can be simultaneously known.

"The uncertainty principle explains why electrons do not simply fall into the nucleus."

"energy level"

A discrete, fixed value of energy that a quantum system such as an electron in an atom can possess.

"When an electron drops to a lower energy level, it emits a photon of specific wavelength."

"photoelectric effect"

The emission of electrons from a material when light of sufficient frequency strikes its surface.

"Einstein's explanation of the photoelectric effect provided key evidence for the quantum nature of light."

"spin"

An intrinsic angular momentum property of subatomic particles, quantised in discrete values.

"Electrons have spin-½, meaning they can be in a spin-up or spin-down state."

"quantum tunnelling"

The quantum mechanical phenomenon where a particle passes through a potential energy barrier it classically could not overcome.

"Nuclear fusion in stars is possible because of quantum tunnelling through the Coulomb barrier."

"diffraction"

The bending and spreading of waves as they pass through an aperture or around an obstacle.

"Diffraction of radio waves around hills allows reception in valleys."

"refraction"

The change in direction of a wave as it passes from one medium into another of different density.

"Refraction causes a straw to appear bent when placed in a glass of water."

"constructive interference"

The combination of two waves in phase, resulting in a wave of greater amplitude.

"Constructive interference produces the bright fringes in a double-slit experiment."

"polarisation"

The orientation of the oscillations of a transverse wave, particularly light, in a specific direction.

"Polarised sunglasses reduce glare by blocking horizontally polarised light reflected from surfaces."

"resonance"

The phenomenon where a system oscillates with greater amplitude at certain natural frequencies.

"Resonance caused the Tacoma Narrows Bridge to oscillate violently and collapse."

"Doppler effect"

The change in observed frequency of a wave due to relative motion between the source and observer.

"The Doppler effect makes a passing ambulance siren sound higher-pitched as it approaches."

"total internal reflection"

The complete reflection of light at a boundary when it strikes at an angle greater than the critical angle.

"Optical fibres transmit data using total internal reflection to guide light along their length."

"wavelength"

The distance between two consecutive points of the same phase on a wave, such as crest to crest.

"Visible light has wavelengths ranging from approximately 380 nm (violet) to 700 nm (red)."

"spacetime"

The four-dimensional continuum combining three spatial dimensions with time, as described in relativity.

"Massive objects curve spacetime, causing nearby objects to follow curved paths."

"time dilation"

The slowing of time experienced by an observer moving at high velocity or in a strong gravitational field.

"GPS satellites must correct for time dilation to maintain accurate positioning."

"event horizon"

The boundary around a black hole beyond which nothing, not even light, can escape.

"Once matter crosses the event horizon, it cannot return to the external universe."

"gravitational lensing"

The bending of light from a distant source by the gravitational field of a massive object.

"Astronomers use gravitational lensing to study galaxies too faint to observe directly."

"dark matter"

An undetected form of matter that does not emit light but exerts gravitational effects on visible matter.

"The rotation curves of galaxies suggest that dark matter accounts for most of their mass."

"redshift"

The increase in wavelength of electromagnetic radiation from an object moving away from the observer.

"The redshift of distant galaxies provided the first evidence for an expanding universe."

"singularity"

A point in spacetime where curvature and density become infinite, such as at the centre of a black hole.

"General relativity predicts a singularity at the core of every black hole."

"cosmic microwave background"

The faint thermal radiation permeating the universe, a remnant of the hot early universe about 380,000 years after the Big Bang.

"Precision measurements of the cosmic microwave background have confirmed the standard model of cosmology."