Sound, pitch & vibrations
Take your time. Show your thinking.
1. How does sound travel from a ringing bell to your ear: vibrations pass from particle to particle through the air as a sound wave, or tiny pieces of metal fly into your ear?
Amplitude (Loudness) · Frequency (Pitch) 2. When you speak or sing and gently rest your fingers on the front of your throat, what do you feel vibrating inside your voice box (larynx): your vocal cords, or your collarbone?
Amplitude (Loudness) · Frequency (Pitch) 3. How do bats and dolphins use echolocation (sonar) to find prey in the dark or deep water: they emit high-pitched clicks and time how long the echoes take to bounce back, or they use magnets?
Amplitude (Loudness) · Frequency (Pitch) 4. When a guitarist tightens a guitar string to increase its tension, what happens to the pitch of the note: the pitch becomes higher, or the string stops vibrating?
Amplitude (Loudness) · Frequency (Pitch) 5. Why are cinema walls and recording studios lined with soft foam, curtains and carpets: soft, porous materials absorb sound waves to prevent echoes, or soft foam makes sounds louder?
Amplitude (Loudness) · Frequency (Pitch) 6. What is the approximate frequency range of normal human hearing in young people: 20 Hz to 20,000 Hz, or 1 Hz to 5 Hz?
Amplitude (Loudness) · Frequency (Pitch) 7. If you hit a drum harder so the drum skin vibrates with a larger amplitude, what happens to the sound: the sound gets louder (higher volume), or the pitch changes into a flute?
Amplitude (Loudness) · Frequency (Pitch) 8. What unit is used in science to measure the frequency of a sound wave (the number of vibrations per second): hertz (Hz) or newtons (N)?
Amplitude (Loudness) · Frequency (Pitch) 9. What unit is used on a sound-level meter to measure the loudness (intensity level) of a sound: decibels (dB) or degrees Celsius (°C)?
Amplitude (Loudness) · Frequency (Pitch) 10. When you blow across the top of two identical glass bottles—one nearly full of water and one nearly empty—which bottle produces the higher-pitched note: the bottle with more water (because the vibrating air column is shorter), or the empty bottle?
Amplitude (Loudness) · Frequency (Pitch) 11. Why do ramp workers near jet engines and operators of loud machinery wear ear defenders (earmuffs): very loud sounds can permanently damage the sensitive hair cells in the inner ear (cochlea), or to keep their ears warm?
Amplitude (Loudness) · Frequency (Pitch) 12. What do we call high-frequency sound waves above 20,000 Hz that humans cannot hear, used by dolphins, bats and medical scanners: ultrasound or infrared?
Amplitude (Loudness) · Frequency (Pitch)