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Q 01 / 25
Sound can travel through a vacuum.
Q 02 / 25
The unit of frequency is Hertz (Hz).
Q 03 / 25
Sound waves in air are longitudinal waves.
Q 04 / 25
Humans can hear sounds of frequency 5 Hz.
Q 05 / 25
The amplitude of a sound wave determines its pitch.
Q 06 / 25
The cochlea in the ear helps convert sound vibrations to nerve signals.
Q 07 / 25
Sound travels faster in air than in water.
Q 08 / 25
Bats use ultrasound to locate prey.
Q 09 / 25
Loud sounds can damage our hearing.
Q 10 / 25
Velocity of sound is constant in all mediums.
Q 11 / 25
Sound reflected from a distant barrier is called an echo.
Q 12 / 25
SONAR is used to detect objects under water.
Q 13 / 25
All musical sounds are a result of regular vibrations.
Q 14 / 25
Noise is produced by irregular vibrations.
Q 15 / 25
Sound does not need a medium for propagation.
Q 16 / 25
Reverberation is the persistence of sound due to multiple reflections.
Q 17 / 25
Pitch of sound depends on its amplitude.
Q 18 / 25
The part of the ear that vibrates when sound reaches it is called the eardrum.
Q 19 / 25
Higher amplitude means lower loudness.
Q 20 / 25
Rarefactions are regions of high pressure in a sound wave.
Q 21 / 25
Ultrasound waves are above 20,000 Hz frequency.
Q 22 / 25
Sound travels faster in solids than in liquids.
Q 23 / 25
Birds use sound for communication.
Q 24 / 25
Frequency of a sound wave changes when it enters a new medium.
Q 25 / 25
Musical instruments produce sound by vibrating air, strings, or membranes.
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