மின்காந்தவியல்: அடிப்படைக் கருத்துக்கள்

• Electromagnetism is a fundamental force of nature that describes the interaction between electrically charged particles

Electromagnetic Force

• It acts between charged particles
• It is the force that causes like-charged substances to repel and oppositely charged substances to attract
• It is a long-range force
• It is responsible for many of the phenomena of daily life

Electric Charge

• It is a fundamental property of matter that causes it to experience a force when placed in an electromagnetic field
• Electric charge can be positive or negative
• Like charges repel each other, and opposite charges attract each other
• The SI unit of electric charge is the coulomb (C)

Electric Field

• It is a region of space around an electrically charged object in which a force would be exerted on other electrically charged objects
• Electric fields are produced by electric charges
• The electric field is a vector field
• The direction of the electric field is the direction of the force that would be exerted on a positive charge placed in the field
• The SI unit of electric field strength is volts per meter (V/m) or newtons per coulomb (N/C)

Electric Potential

• It is the electric potential energy per unit charge at a specific location
• It is a scalar quantity
• The SI unit of electric potential is the volt (V)
• Electric potential difference is commonly referred to as voltage

Electric Current

• It is the rate of flow of electric charge through a conductor
• It is typically carried by electrons moving through a wire
• The SI unit of electric current is the ampere (A), which is equal to one coulomb per second

Magnetism

• It is a force of attraction or repulsion that arises between electrically charged particles because of their motion
• Magnetic fields are produced by moving electric charges
• The magnetic field is a vector field
• The direction of the magnetic field is the direction of the force that would be exerted on a moving positive charge placed in the field
• The SI unit of magnetic field strength is the tesla (T)

Magnetic Force

• It is the force exerted on a moving charge within a magnetic field
• The magnetic force is perpendicular to both the velocity of the charge and the magnetic field
• It is responsible for phenomena such as the deflection of charged particles in magnetic fields and the operation of electric motors

Electromagnets

• They are a type of magnet in which the magnetic field is produced by an electric current
• They are typically made by winding a wire into a coil
• They can be turned on and off by controlling the electric current
• They are used in a wide variety of applications, such as electric motors, generators, and magnetic levitation trains

Electromagnetic Induction

• It is the production of an electromotive force (EMF) across an electrical conductor in a changing magnetic field
• This phenomenon is described by Faraday's law of induction
• It is the principle behind the operation of electrical generators, transformers, and inductors

Maxwell's Equations

• They are a set of four equations that describe the behavior of electric and magnetic fields
• Gauss's law for electricity relates the electric field to the distribution of electric charges
• Gauss's law for magnetism states that there are no magnetic monopoles
• Faraday's law of induction relates a changing magnetic field to an electric field
• Ampere's law relates a magnetic field to an electric current and a changing electric field
• They are the foundation of classical electromagnetism
• They explain a wide range of phenomena, including the behavior of light and radio waves

Electromagnetic Waves

• They are disturbances in electric and magnetic fields that propagate through space
• They are created by accelerating electric charges
• They are transverse waves
• They consist of oscillating electric and magnetic fields that are perpendicular to each other and to the direction of propagation
• They travel at the speed of light in a vacuum
• They include radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, X-rays, and gamma rays

Relationship Between Electricity and Magnetism

• Electricity and magnetism are two aspects of the same fundamental force, electromagnetism
• A changing electric field creates a magnetic field, and a changing magnetic field creates an electric field
• This relationship is described by Maxwell's equations

Applications of Electromagnetism

• Electric motors convert electrical energy into mechanical energy using the interaction between magnetic fields and electric currents
• Generators convert mechanical energy into electrical energy using electromagnetic induction
• Transformers are used to increase or decrease the voltage of alternating current (AC) electricity, enabling efficient power transmission over long distances
• Radio waves are used for wireless communication, broadcasting, and radar
• Microwaves are used for cooking, communication, and radar
• Medical imaging techniques such as MRI (magnetic resonance imaging) rely on strong magnetic fields and radio waves to create detailed images of the human body