The interrelated forces that govern electronics and magnetics.
Electric charge
Electric charge is a fundamental property of matter that describes the interaction between particles and electromagnetic fields. It is measured in coulombs (C): a coulomb is roughly equal to the amount of electric charge carried by 6.24 x 10¹⁸ electrons. Objects can have either a positive or negative electric charge, depending on whether they contain more protons than electrons (positive) or vice versa (negative). Protons carry a positive electrical charge, while neutrons are neutral and do not carry any electrical charge at all.
Opposite charges attract each other due to their electrostatic force, while like charges repel one another as they push away from each other with an equal but opposite force. This phenomenon explains why lightning occurs when clouds become charged with static electricity – the negative charges at the bottom of the cloud are attracted to positive charges on Earth’s surface below it until there is enough energy for them to discharge into a lightning bolt! The same principle applies to magnets; two north poles will repel each other, while two south poles will also repel each other – only when you bring together opposite poles will they be attracted towards one another.
Electric current
Electric current is the flow of electric charge through a material, and it is measured in amperes (A). Direct current (DC) flows in one direction only, while alternating current (AC) reverses its direction periodically. DC is used in batteries to power most electronic devices such as computers and phones, while AC is used in household electricity and powers larger appliances like washing machines and refrigerators.
The difference between direct and alternating currents can be seen when looking at voltage or current plotted against time- DC has a flat line with no variation over time, whereas AC has an oscillating waveform that changes over time. The voltage of AC can be adjusted using transformers to suit different applications. This means that electricity can be distributed nationally at much higher voltages than household supplies, enabling large amounts of power to be moved long distances easily. The voltage of household electricity is 230 V in Europe but 110 V in North America. Additionally, some medical treatments require very low voltages which can only be achieved using AC power sources.
Voltage and potential difference
Voltage is the amount of energy required to move a unit charge from one point to another in an electric field. It can be thought of as the “push” that moves electrons through a circuit and is measured in volts (V). Voltage is related to potential difference, which is the difference in electrical potential between two points.
The voltage between two points can be calculated using Ohm’s law, which states that voltage equals current multiplied by resistance. In this equation, current represents how much charge flows through a material over time while resistance measures how difficult it is for charge to flow through that material. For example, when electricity passes through copper wire with low resistance there will be less voltage drop compared to passing electricity through rubber with high resistance; thus more power will reach its destination when travelling along copper wires rather than rubber ones!
In addition, voltage has an inverse relationship with capacitance – meaning that increasing capacitance decreases voltage and vice versa. Capacitors are components used in circuits which store electrical energy and release it when needed; they are often found in electronic devices such as TVs or computers where they help regulate power supply levels.
Electric circuits
Electric circuits are pathways for electrical current to flow through, and they can be either open or closed. In a closed circuit, the electric current is able to travel in a continuous loop from one point back to its starting point. Insulators are materials that do not allow electricity to pass through them easily, while conductors allow electricity to move freely. Examples of insulating materials include rubber and plastic, while copper and aluminum are examples of conducting materials.
When an electric circuit is broken due to a faulty connection or other issue, it will cause the current flow in the circuit to stop completely. Faults in circuits can lead to damage in electronic devices as well as potential safety hazards such as fires or shocks. Series circuits have components connected end-to-end so that all parts receive the same amount of voltage; parallel circuits have components connected side-by-side so that each component receives its own voltage level independently from others. Both types of circuits have their advantages and disadvantages depending on what type of device they’re used for – series circuits tend to be more efficient but require more maintenance than parallel ones!
Ohm's law
Ohm’s law states that the current in an electrical circuit is directly proportional to the voltage and inversely proportional to the resistance. This means that if you increase the voltage, then more current will flow through a given resistance; conversely, if you decrease the resistance, then more current will flow for a given voltage. Resistance can be thought of as a measure of how difficult it is for electricity to pass through something – materials like copper are good conductors because they have low resistances while materials like rubber are insulators because they have high resistances.
The unit of measurement for resistance is ohms (Ω), named after Georg Ohm who first formulated this law in 1827. The formula V = IR describes this relationship between voltage (V), current (I) and resistance (R). For example, if we know that there’s 10 volts across a resistor with 5 ohms of resistance, then we can calculate that 2 amps of current must be flowing through it using Ohm’s law: 10V/5Ω = 2A.
It’s important to note that not all components obey Ohm’s law – transistors and diodes are two examples which do not follow this equation due to their non-linear behavior.
Capacitance
Capacitance is the ability of a material to store electrical charge. It is measured in Farads (F), which are equal to one coulomb per volt (C/V). Capacitors are components that use capacitance to store and release energy, and they can be found in almost all electronic circuits. They consist of two conductive plates separated by an insulating material called a dielectric, which allows them to hold onto electric charge for longer periods of time than other components.
Capacitors have many uses in electronics, such as filtering out unwanted signals or providing short bursts of power when needed. For example, they can be used as part of a circuit that regulates the voltage supplied from a battery – this helps protect sensitive devices like computers from sudden surges or drops in voltage. Additionally, capacitors are often used with inductors to create simple oscillators – these generate alternating current at specific frequencies and are essential for certain types of radio transmission.
Inductance
Inductance is the tendency of a material to oppose changes in electric current, measured in henrys (H). It is caused by the magnetic field generated when an electric current passes through a conductor.
This phenomenon is known as Faraday’s law of induction and it states that an electromotive force will be induced in any circuit which contains a changing magnetic field. Inductors are components used to store energy in electrical circuits, usually consisting of coils or loops of wire wrapped around a core made from iron or ferrite. Inductors are often used to filter out unwanted signals or to make transformers.
They can also be used as sensors – for example, inductive sensors are often used in traffic lights. Induction motors harness inductance to create mechanical energy using a rotating magnetic field.
Inductance is inversely proportional to frequency – that is, if the frequency of an electric current goes up, inductance goes down.
Electric Fields and magnetic fields
Electric fields are generated by electric charges, and can be visualized as lines of force radiating outward from the charge. These fields exert a force on other charged particles in their vicinity, causing them to move or accelerate. Electric fields have both magnitude and direction, and can be measured using an instrument called an electrometer. Magnetic fields are similar, but describe the influence of magnetic force. A magnetic field is created when electric current flows through a conductor such as a wire.. The Earth’s magnetic field is believed to originate from its molten iron core which generates electrical currents due to convection within it.
Magnetic fields and electric fields move at right angles to each other. The combined electromagnetic force acting on a charged particle is known as Lorentz Force – this is responsible for many phenomena such as magnetism in materials like iron, induction motors used in everyday appliances like washing machines, and even auroras! In addition to these effects on matter itself, electromagnetic radiation (EMR) also results from interactions between electric and magnetic fields – this includes visible light but also radio waves used for communication purposes.
Faraday's law
Michael Faraday’s law of electromagnetic induction states that a changing magnetic field induces an electric current in a conductor. This phenomenon was discovered by Faraday in 1831, when he observed that moving a magnet near a coil of wire caused electricity to flow through the wire. This discovery revolutionized electrical engineering and led to the development of many modern technologies such as generators, transformers, and induction motors.
Induction motors are used extensively today for powering appliances like mixers and air conditioners due to their efficiency and reliability.
They work on the principle of electromagnetic induction – when alternating current passes through coils inside the motor, it creates a magnetic field which rotates in synchronicity with the oscillating current. This in turn causes a rotor element to rotate – sometimes at very high speed – 3600 revolutions per minute is common in some motors.The speed can be controlled by varying the frequency or voltage applied to its windings.
Faraday’s law has also been used in medical imaging technology such as Magnetic Resonance Imaging (MRI) scanners which use powerful magnets and radio waves to create detailed images of internal organs without any invasive procedures.
Lenz's law
Lenz’s law is a fundamental principle of electromagnetism that states the direction of an induced current is always such that it opposes the change in magnetic flux which produced it. This can be seen as analogous to Newton’s third law of motion, which states for every action there is an equal and opposite reaction.
For example, when a magnet moves towards a coil of wire, the changing magnetic field induces an electric current in the wire according to Faraday’s law. According to Lenz’s law, this induced current will flow in such a way as to oppose the magnetic flux of the magnet – creating a repulsive force between them.
The principles behind Lenz’s law have been used extensively in modern technology from MRI scanners and induction motors, to AC generators and metal detectors.
