4.4 Sound Waves

• What is the term for the area in a sound wave where particles are spread out, decreasing pressure?

  Rarefaction
• Sound waves are produced when a vibrating object creates disturbances in a medium
• What is the definition of frequency in sound waves?

  Cycles per second
• What is the definition of wavelength in sound waves?

  Distance between compressions
• The speed of sound depends on the properties of the medium
• The unit of frequency is meters per second.

  False
• What is the rate of wave propagation in sound waves called?

  Speed
• What is the term for the area in a sound wave where particles are pushed together, increasing pressure?

  Compression
• What type of wave are sound waves?

  Longitudinal
• Order the steps of sound wave generation:

  1️⃣ Vibrating Source: A vibrating object sets particles in the medium in motion.

  2️⃣ Compression Formation: Particles close to the source compress together.

  3️⃣ Rarefaction Formation: As particles move back, they spread apart.

  4️⃣ Wave Propagation: These compressions and rarefactions travel through the medium as a longitudinal wave.
• The formula relating frequency, speed, and wavelength is \( f = \frac{v}{\lambda} \), where \( f \) is frequency
• What is the distance between two consecutive compressions or rarefactions called?

  Wavelength
• Sound waves can travel through a vacuum.

  False
• Compressions in sound waves occur where particles are pushed together, increasing pressure
• Steps in the generation of sound waves

  1️⃣ Vibrating Source

  2️⃣ Compression Formation

  3️⃣ Rarefaction Formation

  4️⃣ Wave Propagation
• What is the definition of frequency in sound waves?

  Cycles per second
• The formula for wavelength is \( \lambda = \frac{v}{f} \)

  True
• What properties of a medium affect the speed of sound?

  Density and temperature
• What frequency range is associated with bass sounds?

  20 - 250 Hz
• The loudness of sound is proportional to the square of its amplitude
• Lower density in a medium increases the speed of sound
• What type of waves are sound waves?

  Longitudinal
• Sound waves create areas of compression and rarefaction
• Sound waves create areas of compression and rarefaction
• What occurs during compression in a sound wave?

  Particles are pushed together
• What is the wavelength of a sound wave?

  Distance between compressions
• Match the sound wave property with its definition:

  Frequency ↔️ Number of cycles per second

  Wavelength ↔️ Distance between compressions

  Speed ↔️ Rate of wave propagation
• What is the relationship between amplitude and loudness?

  Loudness ∝ Amplitude²
• The speed of sound in water is approximately 1480 m/s.
• In gases, higher temperature increases the speed of sound.
• Solids have the highest speed of sound due to their high density and elasticity
• Match the medium with its density and speed of sound:

  Air ↔️ 1.225 kg/m^3 and 343 m/s

  Water ↔️ 1000 kg/m^3 and 1480 m/s

  Steel ↔️ 7850 kg/m^3 and 5100 m/s
• What is an example of a longitudinal wave?

  Sound waves
• Sound refraction happens when a sound wave bends as it passes from one medium to another.


  True
• Sound reflection is analogous to light reflecting off a mirror.


  True
• In echolocation, the source of sound waves is animals like bats and dolphins
• What type of waves are sound waves?

  Longitudinal waves
• What are the two types of regions created by sound waves in a medium?

  Compressions and rarefactions
• What are the two properties of a medium that affect the speed of sound?

  Density and temperature
• What does the amplitude of a sound wave determine?

  Loudness