ICT

Transistor

A semiconductor device used to control the flow of electrical current.

NPN Transistor

A type of BJT transistor commonly used as an electronic switch.

Parts of an NPN transistor

Includes Base (controls transistor), Collector (current enters), Emitter (current leaves).

NPN transistor as a switch

Can be OFF (little base current), ON (sufficient base current), or in Saturation (fully ON).

Application of NPN transistors

Used for turning LEDs on/off, controlling motors, amplifying signals.

Potentiometer

A variable resistor whose resistance can be adjusted, used as an adjustable voltage divider.

Parts of a potentiometer

Comprises 3 terminals: Terminal 1, Terminal 2, and Wiper.

Capacitor

An electronic component that stores electrical energy in an electric field.

Unit of capacitance

Measured in farads (F), with subunits like microfarads (µF), nanofarads (nF).

Inductor

Stores energy in a magnetic field, typically consisting of a coil of wire.

Unit of inductance

Measured in henries (H), with common subunits like millihenry (mH).

Diode

A semiconductor device that allows current to flow mainly in one direction.

Ohm's Law

Describes the relationship between voltage, current, and resistance, given by V = IR.

Total Resistance in Series

Calculated as the sum of individual resistances: Rₜ = R₁ + R₂ + R₃.

Total Resistance in Parallel

Calculated using the formula: 1/Rₜ = 1/R₁ + 1/R₂ + … .