6.2.2 Properties of Electromagnetic Waves

• Electromagnetic waves can travel through a vacuum
• Electromagnetic waves consist of oscillating electric and magnetic fields.
• Electromagnetic waves transfer energy without the need for a physical medium
• What is an example of an electromagnetic wave that can travel through space?

  Light
• The electromagnetic spectrum is ordered by wavelength and frequency.
• Match the wave type with its typical use:

  Radio Waves ↔️ Communication

  Microwaves ↔️ Cooking

  Visible Light ↔️ Human Vision

  X-Rays ↔️ Medical Imaging
• Why are electromagnetic waves considered transverse waves?

  Fields oscillate perpendicularly
• The electric and magnetic fields in electromagnetic waves oscillate at right angles to each other and to the direction of wave propagation.
• The oscillating electric and magnetic fields in electromagnetic waves are perpendicular to each other and to the direction of propagation
• What is an example of a transverse electromagnetic wave?

  Light
• What is the formula relating the speed of light, frequency, and wavelength of an electromagnetic wave?

  $c =$$f\lambda$
• The speed of light in a vacuum is approximately $3.0 \times 10^{8} \text{ m / s}$
• The electromagnetic spectrum is ordered by wavelength and frequency.
• Match the wave type with its typical use:

  Radio Waves ↔️ Communication

  Microwaves ↔️ Cooking, Radar

  Infrared ↔️ Thermal Imaging

  Visible Light ↔️ Human Vision
• What type of waves are electromagnetic waves?

  Transverse
• The oscillating electric and magnetic fields in electromagnetic waves are perpendicular to each other and to the direction of propagation
• Electromagnetic waves maintain a constant speed in a vacuum regardless of their wavelength or frequency.
• What is the formula for the energy of an electromagnetic wave in terms of its frequency?

  $E =$$hf$
• Planck's constant is approximately $6.626 \times 10^{ - 34} \text{ J s}$
• Order the electromagnetic waves from longest to shortest wavelength:

  1️⃣ Radio Waves

  2️⃣ Microwaves

  3️⃣ Infrared

  4️⃣ Visible Light

  5️⃣ Ultraviolet

  6️⃣ X-Rays

  7️⃣ Gamma Rays
• Arrange the electromagnetic waves in order of increasing frequency

  1️⃣ Radio waves

  2️⃣ Microwaves

  3️⃣ Infrared

  4️⃣ Visible light

  5️⃣ Ultraviolet

  6️⃣ X-rays

  7️⃣ Gamma rays
• The relationship between the speed of light ($c$), frequency ($f$), and wavelength (\lambda</latex>) is given by $c =$$f\lambda$
• What is the approximate value of the speed of light in a vacuum?

  $3.0 \times 10^{8} \text{ m / s}$
• Radio waves have a wavelength greater than 1 mm
• What is the typical use of microwaves?

  Cooking, Radar
• Infrared waves have a frequency range of 300 GHz - 430 THz
• Visible light is the only part of the electromagnetic spectrum that humans can see
• What is the wavelength range of ultraviolet waves?

  10 nm - 400 nm
• Match the wave type with its typical use:

  Radio Waves ↔️ Communication

  Microwaves ↔️ Cooking, Radar

  Infrared ↔️ Thermal Imaging

  Visible Light ↔️ Human Vision
• Which electromagnetic waves are used in medical imaging?

  X-Rays
• Gamma rays have a wavelength less than 0.01 nm
• Electromagnetic waves are transverse waves because their electric and magnetic fields oscillate perpendicularly to the wave's propagation direction
• What is the orientation of the electric and magnetic fields in a transverse electromagnetic wave?

  Perpendicular
• What is the speed of all electromagnetic waves in a vacuum?

  $3.0 \times 10^{8} \text{ m / s}$
• The speed of electromagnetic waves in a vacuum is constant and approximately 3.0 \times 10^{8} \text{ m / s}</latex>
• Electromagnetic waves travel at a constant speed in a vacuum, known as the speed of light
• What is the approximate value of the speed of light in a vacuum?

  $3.0 \times 10^{8} \text{ m / s}$
• Radio waves, microwaves, visible light, and gamma rays all travel at the same speed in a vacuum.
• In the formula $E =$$hf$, $h$ represents Planck's constant
• What is the approximate value of Planck's constant?

  $6.626 \times 10^{ - 34} \text{ J s}$