Electric current is the flow of electric charge, typically carried by electrons.
Voltage is the potential difference that drives electric current.
Resistance opposes the flow of electric current.
Ohm’s law states that the current through a conductor is directly proportional to the voltage across it, and inversely proportional to its resistance.
In a series circuit, the same current flows through all components.
In a parallel circuit, the voltage across all components is the same, but the current can vary.
A circuit breaker is a safety device that automatically opens a circuit when too much current flows through it.
A fuse is a safety device that contains a metal wire that melts and breaks the circuit if too much current flows through it.
Electric power is the rate at which electric energy is converted into other forms of energy, measured in watts (W).
The unit of electric energy is the watt-hour (Wh) or kilowatt-hour (kWh).
The power consumed by a device can be calculated using the formula P = VI, where P is power, V is voltage, and I is current.
An electric field is a region around a charged object where it can exert a force on other charged objects.
Electric field lines represent the direction and strength of an electric field.
Like charges repel each other, while opposite charges attract.
Conductors allow the easy flow of electric charge, while insulators resist the flow of electric charge.
Charging by conduction involves direct contact between a charged object and an uncharged object.
Charging by induction involves bringing a charged object near an uncharged object, causing a temporary separation of charges.
The nucleus of an atom contains protons and neutrons, while electrons orbit around the nucleus.
Protons have a positive charge, electrons have a negative charge, and neutrons are neutral.
The electric force between charges follows Coulomb’s law, which states that the force is directly proportional to the product of the charges and inversely proportional to the square of the distance between them.
The SI unit of electric charge is the coulomb (C).
Coulomb’s law applies to point charges and can be used to calculate the electric force between them.
Electric potential energy is the energy stored in a system due to the arrangement of charges.
Electric potential (voltage) is the electric potential energy per unit charge.
A capacitor stores electric potential energy in an electric field between its plates.
Capacitance is the ability of a capacitor to store charge and is measured in farads (F).
The time constant of an RC circuit is the time it takes for the charge or discharge of a capacitor to reach about 63.2% of its maximum value.
A diode is an electronic component that allows current to flow in one direction only.
A transistor is a semiconductor device that can amplify or switch electronic signals and electrical power.
Direct current (DC) flows in one direction, while alternating current (AC) periodically changes direction.
Magnetism is the property of a material that responds to the presence of a magnetic field.
Magnetic fields are created by moving charges or by the alignment of magnetic domains in a material.
A magnetic field exerts a force on a moving charged particle.
The strength of a magnetic field is measured in teslas (T).
A transformer is an electrical device used to change the voltage of an alternating current.
Electromagnetic induction is the process of generating an electromotive force (emf) in a circuit by changing the magnetic field.
Faraday’s law of electromagnetic induction states that the induced emf is proportional to the rate of change of magnetic flux through a circuit.
Lenz’s law states that the direction of the induced current in a circuit is such that it opposes the change that produced it.
The electromagnetic spectrum includes all electromagnetic waves, ranging from radio waves to gamma rays.
Light is a form of electromagnetic radiation with properties of both waves and particles (photons).
The speed of light in a vacuum is approximately 3.00 x 10^8 meters per second (m/s).
Refraction is the bending of light as it passes from one medium to another at an angle.
Reflection is the bouncing back of light when it strikes the surface of a material.
The angle of incidence is equal to the angle of reflection for reflected light.
Total internal reflection occurs when light traveling in a dense medium strikes the boundary with a less dense medium at an angle greater than the critical angle.
Diffraction is the bending of waves around obstacles and the spreading of waves as they pass through openings.
The index of refraction of a medium is a measure of how much light slows down in that medium compared to a vacuum.
Snell’s law relates the angle of incidence and the angle of refraction to the indices of refraction of two media.
The focal length of a lens is the distance between the lens and its focal point.
Convex lenses converge light rays and are thicker in the center.
Concave lenses diverge light rays and are thinner in the center.
A converging lens forms real and inverted images when the object is placed beyond its focal point.
A diverging lens forms virtual and upright images.
The critical angle is the angle of incidence that produces an angle of refraction of 90 degrees in a medium.
The electromagnetic spectrum includes radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, X-rays, and gamma rays.
Light exhibits both wave-like and particle-like properties, known as wave-particle duality.
The photoelectric effect is the emission of electrons from a material when light of a certain frequency or higher strikes it.
Photons are discrete packets of electromagnetic energy.
The energy of a photon is directly proportional to its frequency and inversely proportional to its wavelength.
The wave function in quantum mechanics describes the probability distribution of a particle’s position and momentum.
The Heisenberg uncertainty principle states that the more precisely the position of a particle is known, the less precisely its momentum can be known, and vice versa.
Quantum numbers describe the properties and energy levels of electrons in an atom.
The Pauli exclusion principle states that no two electrons in an atom can have the same set of quantum numbers.
The Aufbau principle dictates the order in which electrons fill atomic orbitals.
Hund’s rule states that electrons will occupy degenerate orbitals singly before pairing up.
Quantum mechanical models of the atom describe electrons as existing in orbitals rather than fixed paths.
The electron configuration of an atom describes the distribution of electrons in its orbitals.
