La Rioja PAU Tech & Engineering II (UR) key terms

The maximum stress a material can withstand without permanent deformation; beyond this point, it does not return to its original shape when unloaded.

The stress at which a material begins to deform plastically, typically determined by the 0.2% offset method for metals without a clear yield point.

A destructive test where a specimen is pulled until failure to determine properties like yield strength, ultimate tensile strength, and elongation.

A graph plotting stress against strain for a material, revealing its stiffness, strength, ductility, and toughness.

A measure of a material's stiffness, defined as the ratio of tensile stress to tensile strain in the linear elastic region.

The principle stating that stress is directly proportional to strain within the elastic limit of a material.

The ratio of a material's ultimate strength to the allowable working stress, used to ensure safety against failure.

The maximum stress considered safe for design, calculated by dividing the material's strength by a factor of safety.

The internal moment that causes a beam to bend, equal to the sum of moments about a section from external forces on one side.

The internal force acting parallel to a cross-section of a beam, tending to cause sliding between adjacent parts.

A geometric property of a cross-section equal to the moment of inertia divided by the distance from the neutral axis to the extreme fiber; used to calculate bending stress.

A measure of a shape's resistance to bending about an axis, equal to the sum of areas times the square of their distance from the axis.

A mechanism consisting of four rigid links connected by four pin joints, used to convert rotary motion into oscillating or complex motion.

The number of independent parameters needed to define the position of a mechanism; for planar mechanisms, calculated using Grübler's criterion.

The ratio of the number of teeth on two meshing gears, which determines the relationship between their speeds and torques.

A twisting force that tends to cause rotation, calculated as force multiplied by the perpendicular distance from the pivot.

The relationship stating that current through a conductor is directly proportional to voltage and inversely proportional to resistance.

Two rules for circuit analysis: the current law (sum of currents at a node is zero) and the voltage law (sum of voltages around a loop is zero).

A circuit where components are connected end-to-end, so the same current flows through all of them and the total voltage is the sum of individual voltages.

A circuit where components are connected across the same voltage, so the total current is the sum of branch currents and the voltage is the same across each branch.

The ratio of real power to apparent power in an AC circuit, indicating how effectively electrical power is converted into useful work.

The product of RMS voltage and RMS current in an AC circuit, measured in volt-amperes (VA), representing the total power supplied.

The power that oscillates between source and load in an AC circuit, measured in volt-amperes reactive (VAR), due to inductive or capacitive elements.

A programmable logic controller is an industrial digital computer used to automate electromechanical processes, executing control logic based on input signals.

A graphical programming language for PLCs that uses contacts and coils arranged in rungs to represent logical control circuits.

A device that detects a physical quantity (e.g., temperature, light, position) and converts it into a signal usable by a control system.

A device that converts a control signal into physical motion or action, such as a motor, solenoid, or pneumatic cylinder.

A control loop mechanism using proportional, integral, and derivative terms to minimize error between a measured process variable and a setpoint.

A control system that uses feedback from sensors to compare actual output with the desired setpoint and adjust the input accordingly.

A method of representing a 3D object by projecting its features onto two or more perpendicular planes, typically showing front, top, and side views.

A standard orthographic projection system (ISO) where the object is placed between the observer and the projection plane, used mainly in Europe.

The process of adding measurements, tolerances, and notes to a technical drawing to specify the size and location of features.

The permissible variation in a dimension, indicating the acceptable range between upper and lower limits for manufacturing.

The relationship between the sizes of two mating parts (e.g., clearance, interference, transition) before assembly, determined by their tolerances.

Computer-aided design is the use of software to create, modify, analyze, and document 2D and 3D models of physical parts and assemblies.

A horizontal bar chart that visually schedules project tasks over time, showing start and end dates, durations, and dependencies.

The process of defining project scope, sequencing activities, estimating resources and durations, and creating a schedule to achieve objectives.

An itemized estimate of expected income and expenses for a project, used to allocate resources and control costs.

Energy derived from natural sources that are replenished at a higher rate than they are consumed, such as solar, wind, hydro, and biomass.

The ratio of useful output of a system to the energy input, often expressed as a percentage; higher efficiency means less energy wasted.