Sound Flashcards
What causes sound?
Sound is caused by vibrations.
How does sound travel to our ears?
Sound travels to our ears as longitudinal waves.
When we make a sound, we push air molecules, creating compressions and rarefactions that travel across the room to our ears.
Can sound travel without air?
No, sound cannot travel without air. Sound waves need a medium, like air, to travel through. In a vacuum, where there are no particles, sound cannot travel.
In which medium does sound travel the fastest?
Sound travels the fastest in solids.
What is the order of speed of sound in different states of matter from fastest to slowest?
The order is solids, liquids, and then gases.
Why can’t sound travel in a vacuum?
Sound cannot travel in a vacuum because there are no particles to transmit the vibrations.
What happens when there is a storm in terms of sound and light?
During a storm, we first see lightning and then hear thunder because light travels much faster than sound.
How can you find the speed of sound in air using an experiment?
To find the speed of sound in air, measure the distance between two microphones, clap at one end, and use the time it takes for the sound to travel between the microphones to calculate the speed using the formula: Speed
= Distance / Time.
What is an echo?
An echo is a reflection of a sound wave that bounces off a barrier and returns to the source.
How do bats use echoes?
Bats emit high-frequency sounds and use the echoes that bounce back to navigate and find their prey in the dark.
Why can’t humans hear ultrasound?
Humans cannot hear ultrasound because it has a frequency higher than 20,000 Hz, which is beyond the range of human hearing.
How do ships use echoes?
Ships use echoes to determine the depth of the sea or to detect objects underwater by emitting sound waves and measuring the time it takes for the echoes to return.
What is the frequency range that young children can hear?
Young children can hear sounds with frequencies as low as 20 Hz and as high as 20,000 Hz.
How do dolphins use ultrasound?
Dolphins use high-frequency ultrasound waves (up to 150,000 Hz) for echolocation to catch fish and navigate underwater.
How is ultrasound used in medicine?
Ultrasound is used in medicine to create images of the inside of the body. An ultrasonic transmitter/receiver is moved across the skin, and the reflected waves are used to build up a picture on a screen.
