Electronics Flashcards
What are transistors
Transistors are a type of high speed electronic switch. Instead of pressing a button we must send a signal of 0.7 volts to the base leg. Transistors are usually protected by a resistor. The graphic and circuit symbol are shown below.
What are potential dividers
These are made up of two resistors in a line between the positive and negative rails and are used circuits to adjust the voltage. Our main concern when dealing with potential dividers is the value at the vout ( voltage out ) point. The value of the voltage out depends on the value of the resistors
What is an electrical circuit
An electrical circuit is an arrangement of components which allows an electrical current to flow. A circuit may be as simple as a battery connected to a lamp or as complicated as a computer
What’s a basic circuit
This consists of a power supple or source of electrical current and output device and two wires to connect the device to the “ + “ & “ - “ terminals of the source. The part of the circuit performing the work is called the load
What’s a series circuit
Circuits may include more than one component when the current flows through one component and then to another, the components are said to be in series.
What’s a parallel circuits
A parallel circuit is formed when two or more components are connected so that the current can flow through one component without having to glow through another first.
What’s a complex circuit
Most circuits ( however ) have some components in series and others in parallel. The main criteria for a circuit is that there must be a complete path for the current, between the component and the powers supply
What’s a direct current
An electrical current can flow in either of two directions through a conductor. If it flows in one direction, whether it’s a steady stream or in pulses it’s known as direct current. In most electronic products Direct current is used. It is important to be able to specify the quantity and power of a direct current
What’s a current
The quantity of electrons passed a point in one second. The unit of measurements is the ampere or amp
What’s a voltage
The electrical pressure or force. Voltage is sometimes referred to as electromotive force EMF or potential difference. The voltage drop Is the difference in voltage between the two ends of a conductor through which a current passes. The voltage drop across a whole circuit will be equal to the supple voltage. The unit of measurement is the volt
What’s a power
The work performed by an electrical current. The unit of measurement is called the watt. The power is directly proportional to the voltage and the current in a circuit
What’s a resistance
All conductors resist flow of current to some degree. The unit of measurement is the ohm. A potential difference of 1 volt will force a current of 1 amp through a resistance of 1 ohm. The component with the largest resistance in a circuit will have the largest voltage drop across it.
What’s ohms law
The relationship between current, voltage, power and resistance is explained mathematically by ohms law
V=CxR
C=V divided by R
R=V divided by C
P=VxC
P=C squared x R
What’s a power supply
There many types of direct current power supply. The two main types are batteries and mains transformers others include solar cells. The main supply will use will be the battery
