SJVN JFE & FE key terms

The real power actually consumed or delivered by a circuit, measured in watts, equal to voltage times current times the cosine of the phase angle between them.

Power that oscillates between source and reactive elements without doing useful work, measured in volt-amperes reactive (VAR) and caused by inductance or capacitance phase shift.

The ratio of active power to apparent power in an AC circuit, ranging from 0 to 1, indicating how effectively current is converted into useful work.

A static electromagnetic device that transfers electrical energy between two circuits by mutual induction, changing voltage and current levels while keeping frequency essentially unchanged.

The ratio of primary winding turns to secondary winding turns in a transformer, which determines the relationship between input and output voltages.

Circulating currents induced inside a conducting magnetic core by changing magnetic flux, causing energy loss as heat and reduced efficiency in machines.

Energy wasted as heat each time a magnetic material is magnetized and demagnetized through a cycle, depending on the core material and magnetic flux density.

A switching device that automatically interrupts fault current to protect equipment, and can be reset and reclosed, unlike a fuse that must be replaced.

A protective device that senses abnormal electrical conditions such as overcurrent or earth fault and sends a signal to trip a circuit breaker.

Deliberate connection of exposed conductive parts or a neutral point to the ground, providing a low-resistance path for fault current and limiting touch voltage.

An AC machine in which current is induced in the rotor by a rotating magnetic field from the stator, producing torque without any direct electrical rotor connection.

The difference between synchronous speed and actual rotor speed of an induction motor, usually expressed as a percentage of synchronous speed.

The speed of the rotating magnetic field in an AC machine, equal to 120 times frequency divided by the number of poles.

A generating station that burns fuel to produce steam, which drives a turbine coupled to a generator, converting heat energy into electrical energy.

A generating station that converts the potential and kinetic energy of stored or flowing water into electricity using turbines and generators.

An impulse water turbine in which high-velocity jets strike bucket-shaped runners, used for high-head, low-flow hydroelectric installations.

A diverging tube that connects the runner outlet of a reaction turbine to the tailrace, recovering kinetic energy and allowing the turbine to sit above tailwater.

The ideal thermodynamic cycle describing steam power plants, consisting of pumping, constant-pressure heating and boiling, expansion through a turbine, and condensation.

A pressure vessel in which water is heated and converted into steam for driving a turbine or for process use, transferring heat from combustion gases.

The ratio of the ultimate or yield strength of a material to the maximum working stress, indicating how much reserve capacity a design has.

The internal moment at a section of a beam caused by external loads, equal to the algebraic sum of moments of forces about that section.

The internal force acting parallel to the cross-section of a beam at a point, equal to the algebraic sum of transverse forces on one side of the section.

Internal resistance per unit area developed within a material when it is subjected to external loads, commonly expressed in megapascals.

The deformation of a material per unit of its original length, a dimensionless measure of how much it stretches or compresses under load.

A designation such as M25 that indicates the characteristic compressive strength of concrete in newtons per square millimetre at 28 days.

A basic digital circuit element such as AND, OR, NOT, NAND or NOR that produces a defined output based on combinations of binary input levels.

A mathematical system of binary variables and logical operations used to simplify and design digital logic circuits and switching functions.

A bistable digital storage element that holds one bit of data and changes state in response to clock or control inputs.

An electronic circuit using diodes or controlled switches that converts alternating current into unidirectional or direct current.

The comparison of two quantities by division and the statement that two such comparisons are equal, used to solve scaling and sharing problems.

A problem-solving technique that first finds the value of one unit and then multiplies to obtain the value of the required number of units.

A fraction or ratio expressed as a part per hundred, widely used to compare quantities and compute increases, decreases and discounts.

The sum of a set of values divided by the number of values, representing a central value used in data interpretation and reasoning problems.

A form of logical reasoning in which a conclusion is drawn from two or more given premises, tested for validity rather than factual truth.

A reasoning topic requiring the candidate to determine family relationships between people from statements describing kinship links.

A reasoning topic involving movement along compass directions, where the candidate tracks position and computes net distance or final facing direction.

A reasoning task in which the missing or next element of a number, letter or figure sequence must be identified from the pattern followed.

A fixed expression whose meaning cannot be deduced from the literal words, understood only through conventional usage in a language.

A word that has the same or nearly the same meaning as another word in the same language, used in vocabulary questions.

A word whose meaning is opposite to that of another word, tested to assess the breadth and precision of a candidate's vocabulary.

Two grammatical constructions where the subject performs the action (active) or receives it (passive), tested through sentence transformation questions.

The reporting of spoken words either exactly as said (direct) or paraphrased with tense and pronoun shifts (indirect), a common grammar test item.