Current refers to the flow of electric charge, measured in units of amperes (A). Voltage is the potential difference between two points, measured in units of volts (V). Resistance is the opposition to the flow of current, measured in units of ohms (Ω).
Power is calculated by multiplying the voltage by the current, or by using the formula P=VI. The unit of power is watts (W).
Ohm's law states that the current through a conductor is directly proportional to the voltage and inversely proportional to the resistance. It is commonly used in electronic circuits to calculate the relationship between voltage, current, and resistance.
AC (alternating current) circuits have a continuously changing direction of current flow, while DC (direct current) circuits have a constant direction of current flow. AC is typically used for long-distance power transmission, while DC is used for electronic devices.
A transistor is a semiconductor device that is used to amplify or switch electronic signals. It has three layers of material - the collector, base, and emitter - and can be controlled by applying a small current to the base, allowing for larger currents to flow between the collector and emitter.