Waves

• What are electromagnetic waves?


  Electromagnetic waves are a type of energy that can travel through space without needing a medium.
• How are electromagnetic waves created?


  They are created by the vibration of electric and magnetic fields.
• What is a key characteristic of electromagnetic waves regarding their travel medium?


  They can travel through a vacuum (empty space).
• What produces electromagnetic waves?


  Electromagnetic waves are produced by charged particles when they accelerate.
• Give an example of an electromagnetic wave.


  Light from the sun is an electromagnetic wave that travels through space to reach Earth.
• What is the electromagnetic spectrum?


  The electromagnetic spectrum is the range of all types of electromagnetic radiation.
• How is the electromagnetic spectrum divided?


  It is typically divided into seven main regions, ordered by increasing frequency and decreasing wavelength.
• What are the seven main regions of the electromagnetic spectrum?


  Radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, and gamma rays.
• What happens to the energy of electromagnetic waves as frequency increases?


  Higher frequency waves have more energy.
• What is the speed of electromagnetic waves in a vacuum?


  All EM waves travel at the speed of light, approximately $3 \times 10^8 \text{ m/s}$.
• What is diffraction in relation to electromagnetic waves?


  Diffraction is when EM waves bend around obstacles or spread out when passing through small openings.
• What is interference in the context of electromagnetic waves?


  Interference occurs when multiple waves interact, either reinforcing or cancelling each other out.
• What is the significance of the speed of light in relation to electromagnetic waves?


  All EM waves travel at the same speed in a vacuum, which is the speed of light.
• What are some applications of radio waves?


  Radio waves are used for communication in radios, TVs, and mobile phones.
• What are microwaves used for?

  Microwaves are used in microwave ovens for cooking and in radar systems.
• What is infrared radiation used for?


  Infrared is used in remote controls and thermal imaging cameras.
• What is visible light used for?


  Visible light is used in photography, lighting, and fiber optic communications.
• What is ultraviolet radiation used for?


  Ultraviolet is used in sterilization and detecting forged banknotes.
• What are X-rays used for?


  1. rays are used in medical imaging to see inside the body.
• What are gamma rays used for?


  Gamma rays are used in some cancer treatments and in studying space.