UAE TLS Physics Subject Test key terms

A vector quantity describing the straight-line change in position from a starting point to an ending point, including both distance and direction. It differs from distance, which is a scalar measuring total path length.

The rate at which velocity changes with time, including changes in speed, direction, or both. It is a vector measured in metres per second squared and can be positive or negative.

The principle that the net force acting on an object equals its mass multiplied by its acceleration. It links force, mass, and acceleration and explains why heavier objects need larger forces to accelerate equally.

The product of an object's mass and its velocity, describing how hard it is to stop the object. It is a vector quantity conserved in any closed system where no external forces act.

The rule that the total momentum of an isolated system stays constant before and after any interaction, such as a collision or explosion. External forces must be absent or negligible for it to hold.

The net force directed toward the centre of a circular path that keeps an object moving in that circle. Without it, the object would travel in a straight line tangent to the path.

The energy transferred to or from an object when a force acts on it through a displacement. It is calculated as force times displacement times the cosine of the angle between them.

The principle that energy cannot be created or destroyed, only transferred or transformed between forms. The total energy of an isolated system remains constant over time.

The energy an object possesses because of its motion, calculated as one half its mass times the square of its speed. Doubling the speed quadruples the kinetic energy.

A simplified drawing showing a single object isolated from its surroundings with all external forces drawn as arrows acting on it. It helps students analyse net force and predict motion.

The number of complete wave cycles passing a fixed point each second, measured in hertz. It is inversely related to period and determines the pitch of a sound or colour of light.

The distance between two consecutive corresponding points on a wave, such as crest to crest or compression to compression. It is measured in metres and relates to frequency and wave speed.

The rate at which a wave disturbance travels through a medium, equal to frequency multiplied by wavelength. It depends on the properties of the medium rather than on the wave's amplitude.

The bending of a wave as it passes from one medium into another where its speed changes. The change in direction occurs because different media slow or speed up the wave differently.

A dimensionless number describing how much a medium slows light compared with its speed in a vacuum. Higher values indicate greater slowing and more bending at a boundary.

The complete reflection of light back into a denser medium when it strikes a boundary beyond the critical angle. It occurs only when light travels from a higher to a lower refractive index medium.

The spreading of waves as they pass through an opening or around an obstacle. It becomes more pronounced when the gap or obstacle is comparable in size to the wavelength.

The principle that when two or more waves meet at a point, the resultant displacement equals the algebraic sum of their individual displacements. It explains interference patterns, beats, and standing waves.

A wave pattern formed when two identical waves travelling in opposite directions superpose, producing fixed nodes and antinodes. It does not transfer energy along the medium.

A large increase in amplitude that occurs when a system is driven at one of its natural frequencies. It underlies musical instruments, tuned circuits, and many mechanical vibrations.

The apparent change in observed frequency of a wave when the source, the observer, or both move relative to the medium. Approaching sources raise pitch; receding sources lower it.

A region around a charged object where another charge experiences a force. Its strength and direction are represented by field lines and measured in newtons per coulomb.

The rule that the electrostatic force between two point charges is proportional to the product of the charges and inversely proportional to the square of the distance between them. It acts along the line joining the charges.

The work done per unit charge in moving a charge between two points in an electric field, measured in volts. It drives current through a conductor when a circuit is closed.

The relationship stating that current through a conductor is directly proportional to the potential difference across it, provided temperature stays constant. The constant of proportionality is resistance.

A measure of how strongly a component opposes the flow of electric current, measured in ohms. It depends on material, length, cross-sectional area, and temperature.

Two ways of connecting components: in series they share one path so current is the same through each, while in parallel they share the same potential difference across each branch.

The generation of an electromotive force in a conductor when it experiences a changing magnetic flux. It is the operating principle behind generators, transformers, and many sensors.

A measure of the number of magnetic field lines passing through a given area, calculated from field strength, area, and the angle between them. Its rate of change drives induced currents.

The rule that an induced current flows in a direction whose magnetic effect opposes the change that produced it. It is a direct consequence of energy conservation in electromagnetic systems.

The total kinetic and potential energy of the particles within a system, arising from their random motion and interactions. It changes with temperature, phase, and the number of particles.

The statement that the heat added to a system equals the change in its internal energy plus the work it does on its surroundings. It is the energy-conservation law applied to thermal processes.

The energy needed to raise the temperature of one kilogram of a substance by one kelvin, measured in joules per kilogram per kelvin. It explains why materials heat up at different rates.

The energy absorbed or released by a substance during a change of phase without any change in temperature. It breaks or forms bonds between particles rather than increasing their kinetic energy.

The lowest possible temperature, zero kelvin, at which particles have minimum kinetic energy. It equals about minus 273 degrees Celsius and cannot be reached exactly in practice.

The equation relating pressure, volume, temperature, and amount of gas for an idealised gas in which particles have negligible size and no intermolecular forces. It is written as pressure times volume equals amount times gas constant times temperature.

The emission of electrons from a metal surface when light of sufficiently high frequency strikes it. It provides evidence that light delivers energy in discrete packets called photons.

A discrete packet of electromagnetic energy whose energy equals Planck's constant times the wave's frequency. Photons have no rest mass and travel at the speed of light.

The minimum energy required to remove an electron from the surface of a particular metal. It sets the threshold frequency below which no photoelectric emission occurs.

The time required for half of the radioactive nuclei in a sample to decay. It is constant for a given isotope and allows prediction of remaining activity over time.

The spontaneous transformation of an unstable nucleus into a more stable one, emitting alpha, beta, or gamma radiation. The process is random for individual nuclei but predictable for large samples.

The number of nuclear decays occurring per unit time in a radioactive sample, measured in becquerels. It decreases exponentially with time according to the isotope's half-life.

The idea that light and matter exhibit both wave-like and particle-like behaviour depending on the experiment. Interference shows wave nature while the photoelectric effect shows particle nature.

The range within which a measured value is expected to lie, often expressed as plus or minus a stated amount. It reflects limitations of instruments and techniques rather than mistakes.

Precision describes how closely repeated measurements agree with each other, while accuracy describes how close a measurement is to the true value. A result can be precise but inaccurate due to systematic error.

Systematic errors shift all measurements in the same direction, often from faulty instruments or calibration, while random errors scatter measurements unpredictably. Repeating readings reduces random error but not systematic error.

The digits in a measurement that carry meaningful information about its precision, excluding leading zeros. The final answer should be reported to the same precision as the least precise input.

Rearranging data or choosing axis variables so that plotted points form a straight line, making it easier to identify relationships and extract constants from the gradient or intercept.

The slope and vertical-axis crossing of a best-fit line on a graph, which often correspond to physical constants or initial values in an experiment. Their units derive from the axes.

Ongoing evaluation of student understanding during instruction, used to adjust teaching rather than to assign grades. Examples include exit tickets, questioning, and quick concept checks.

Evaluation of student learning at the end of a unit or course, used to judge achievement against standards. It typically takes the form of tests, projects, or practical examinations.

A persistent, intuitively appealing idea that conflicts with accepted scientific understanding, such as believing force is needed to sustain motion. Effective teaching explicitly confronts and restructures such ideas.

An instructional approach in which students investigate questions, design procedures, collect evidence, and construct explanations rather than passively receiving facts. It develops scientific reasoning and investigation skills.

The deliberate matching of intended learning outcomes, teaching activities, and assessment tasks so that what is taught is what is measured. Misalignment weakens the validity of assessment results.

Planning instruction so that students with varied readiness, interests, and learning profiles can access the same core objectives. It may involve varied tasks, scaffolding, or pacing.

Temporary support provided to learners, such as worked examples, prompts, or structured templates, that is gradually removed as competence grows. It targets tasks just beyond independent ability.