12.5 Electromagnetic Waves

• Electromagnetic waves travel at the speed of light in a vacuum.


  True
• What type of wave are electromagnetic waves?

  Transverse wave
• What is the approximate speed of light in a vacuum?

  $3 \times 10^{8} \text{ m / s}$
• What is the common property shared by all electromagnetic waves?

  Transverse waves
• In electromagnetic waves, electric and magnetic fields oscillate perpendicularly to each other and to the direction of wave propagation.


  True
• Unlike mechanical waves, electromagnetic waves do not require a medium
• Electromagnetic waves carry energy, allowing them to transfer heat, light, and other forms of radiation
• Electromagnetic waves travel at a constant speed in a vacuum
• The electric field in an electromagnetic wave sustains the magnetic field.

  False
• All electromagnetic waves propagate at the same speed of light in a vacuum.


  True
• The electric and magnetic fields in electromagnetic waves oscillate perpendicularly to the direction of wave propagation
• In electromagnetic waves, the electric field generates the magnetic field.
• What is the electromagnetic spectrum based on?

  Wavelength and frequency
• What is the frequency range of radio waves?

  < 300 GHz
• What is the wavelength range of visible light?

  400 nm - 700 nm
• The speed of light in a vacuum depends on the wave's frequency.

  False
• Order the following mediums from lowest to highest refractive index:

  1️⃣ Vacuum

  2️⃣ Air

  3️⃣ Water

  4️⃣ Glass
• In electromagnetic waves, the oscillating electric and magnetic fields are mutually induced.
• Electromagnetic waves are created by the oscillation of electric and magnetic
• Electromagnetic waves are classified based on their wavelength and frequency.
• All electromagnetic waves differ in their specific wavelength and frequency
• Do electromagnetic waves require a medium to travel?

  No
• Which type of electromagnetic wave has the longest wavelength?

  Radio Waves
• Electromagnetic waves require a medium to travel.

  False
• The electric and magnetic fields in electromagnetic waves oscillate parallel to each other.

  False
• The electromagnetic spectrum classifies waves based on their wavelength and frequency
• Electromagnetic waves are created by the oscillation of electric and magnetic fields
• In electromagnetic waves, in what direction do electric and magnetic fields oscillate relative to each other?

  Perpendicularly
• Match the property with its description in electromagnetic waves:

  Electric Field ↔️ Perpendicular to wave propagation

  Magnetic Field ↔️ Perpendicular to wave propagation and E
• All electromagnetic waves are transverse waves.

  True
• Match the type of electromagnetic wave with its wavelength range:

  Microwaves ↔️ 1 mm - 1 m

  Infrared ↔️ 700 nm - 1 mm
• X-rays have a wavelength range of 0.01 nm to 10 nm.
• What does the refractive index of a medium quantify?

  Change in wave speed
• The refractive index of vacuum is 1.


  True
• The mutual induction of electric and magnetic fields allows electromagnetic waves to propagate through space.


  True
• Match the type of electromagnetic wave with its wavelength range:

  Radio Waves ↔️ > 1 mm

  Microwaves ↔️ 1 mm - 1 m

  Infrared ↔️ 700 nm - 1 mm

  Visible Light ↔️ 400 nm - 700 nm

  Ultraviolet ↔️ 10 nm - 400 nm

  X-rays ↔️ 0.01 nm - 10 nm

  Gamma Rays ↔️ < 0.01 nm
• What is the constant speed at which electromagnetic waves travel in a vacuum?

  $3 \times 10^{8} \text{ m / s}$
• Match the wave type with its propagation speed:

  Electromagnetic Waves ↔️ Speed of light ($c$)

  Mechanical Waves ↔️ Varies by medium
• Electromagnetic waves carry energy.

  True
• Match the property of electromagnetic waves with its description:

  Speed of Light ↔️ Travels at $3 \times 10^{8} \text{ m / s}$ in a vacuum

  Transverse Nature ↔️ Electric and magnetic fields oscillate perpendicularly

  Energy Transfer ↔️ Carries heat, light, and radiation

  Interaction with Matter ↔️ Absorption, reflection, or transmission