eQuizShow
Waves and Sound
Part of a Wave
Question: The top of a wave
Answer: Peak or Crest
Question: The bottom of a wave
Answer: Trough
Question: The height of a wave.
Answer: Amplitude
Remember amplitude can be measured from the peak or trough to the midline (the line drawn down the middle of the wave).
Question: The distance between two peaks of a wave.
Answer: Wavelength
Question: The number of peaks that pass by in a second.
Answer: Frequency
Types of Waves
Question: A wave where the medium moves perpendicular to the wave.
Answer: Transverse Wave
Example: Ocean Wave
Question: A type of wave where the wave moves the same direction as the medium.
Answer: Compressional or Longitudinal Wave
Example: Sound Wave
Question: Sound is a __________________ wave
Answer: Compressional or Longitudinal wave
Remember: When a speaker moves it pushes and pulls on the air. These pushes and pulls create compressional waves.
Question: Ocean waves are an example of what type of wave?
Answer: Transverse waves.
Question: A slinky can make both types of waves. How do you move a slinky to make a compressional wave?
Answer: Stretch a slinky between two people and move your hand in a push/pull motion.
Sound
Question: What is the cause of all sounds?
Answer: Something vibrating...
Question: Sound must travel in a ________________.
Answer: Medium
Remember: A medium is any substance a wave travels through. A ocean wave travels in the medium of water. Sound can can travel through many kinds of mediums (air/water/steel). But can not travel in outer space (no medium out there!).
Question: What takes more energy to create?
A high pitched sound. - - or - - A low pitched sound.
Answer: A high pitched sound.
Question: It takes <> or <> energy to create a loud sound?
Answer: It take more energy to create a loud sound.
Question: Can sound travel in outer space?
Answer: No.
Sound needs a medium (atoms/molecules) to vibrate. Outer space is a vacuum (no atoms/molecules). Therefore no sound in space. Yup, those exploding space ships in movies don't really make a sound...
Pitch
Question: What three qualities of a sound wave could control the pitch of a sound?
Answer: Frequency (a higher frequency = higher pitch)
Wavelength (a shorter wavelength = higher pitch)
Speed (a faster sound wave = higher pitch)
((The opposite of all the above = lower pitch))
Question: If the speed of a sound is increased what would happen to the pitch of the sound?
Answer: The sound would become higher in pitch.
Question: If the wavelength of a sound is decreased what would happen to the pitch of the sound?
Answer: The sound would become lower in pitch.
Question: If the frequency of a sound is decreased what would happen to the pitch of the sound?
Answer: The sound would become lower in pitch.
Question: The larger the instrument the _____________ the pitch.
Answer: lower
Larger instruments can not vibrate as fast and produce lower pitched sounds.
Volume
Question: What quality of a sound wave controls the loudness or volume of a sound?
Answer: The amplitude of a sound wave controls the loudness of a sound.
Question: When a speaker moves back and forth faster the sound gets louder.
True or False
Answer: False
When a speaker moves back and forth faster the pitch gets higher in pitch (frequency becomes higher).
Question: When a speaker moves back and forth farther the sound gets louder.
True or False
Answer: True
When a speaker moves farther and still remains at the same frequency the sound produced will be louder.
Question: The larger the instrument the _____________ the pitch.
Answer: lower
Larger instruments can not vibrate as fast and produce lower pitched sounds.
Question: It takes <> or <> energy to create a loud sound?
Answer: It take more energy to create a loud sound.