Electromagnetic Radiation and Applications

These flashcards cover the types of electromagnetic radiation, their discoveries, characteristics, and applications in modern technology.

What are electromagnetic waves?

Electromagnetic waves are waves that propagate through space, consisting of electric and magnetic fields oscillating perpendicular to each other and to the direction of propagation.

Who coined the term 'electricus' and studied magnetism systematically?

William Gilbert (1544–1603) coined the term 'electricus' and laid the foundation for the study of electricity and magnetism.

What did Hans Christian Orsted discover?

Hans Christian Orsted discovered that an electric current is surrounded by a magnetic field and that a magnetic needle moves when electric current passes through a nearby wire.

What is electromagnetic induction?

Electromagnetic induction is the phenomenon where a moving wire through a magnetic field generates an electric current.

Who independently discovered electromagnetic induction like Faraday?

Joseph Henry (1797–1878) independently discovered electromagnetic induction.

What is the significance of James Clerk Maxwell's work?

James Clerk Maxwell described how electric and magnetic fields interact and formulated Maxwell's equations, showing that electromagnetic waves travel at the speed of light.

What did Heinrich Hertz confirm through his experiments?

Heinrich Hertz confirmed the existence of electromagnetic waves by applying Maxwell's theory to the production and reception of radio waves.

What are the characteristics of electromagnetic waves?

Electromagnetic waves are transverse waves that can travel through a vacuum and carry energy and information.

What is wavelength in the context of electromagnetic waves?

Wavelength (λ) is the distance between two consecutive crests or troughs of a wave, representing the length of one complete wave cycle.

What forms the electromagnetic spectrum?

The electromagnetic spectrum is the range of all types of electromagnetic radiation, categorized by wavelength or frequency.

What are radio waves and their significance?

Radio waves have the longest wavelengths and low frequencies, essential for modern communication like radio broadcasts, Wi-Fi, and GPS.

How do microwaves function in everyday applications?

Microwaves are used in microwave ovens for cooking food and in communications, having higher frequencies than radio waves.

What is the range of visible light in the electromagnetic spectrum?

Visible light is the portion of the electromagnetic spectrum that can be detected by the human eye and comes in colors ranging from red to violet (ROYGBIV).

What are the health risks associated with ultraviolet (UV) radiation?

Ultraviolet radiation can cause sunburns, skin aging, and increase cancer risks despite being non-ionizing.

What are the uses of X-rays?

X-rays are used in medical imaging and are considered ionizing radiation, capable of passing through soft tissues.

What are gamma rays and their risks?

Gamma rays have the highest energy and are ionizing radiation, potentially causing DNA damage and increasing cancer risk.