General
Sound is a form of
What is the formula for wave speed?
v = fλ
Sound moves as
vibrations
Why can we hear someone around a corner?
Diffraction
What is the difference between infrasonic and ultrasonic?
Infrasonic is anything under 20 Hz
Ultrasonic is anything over 20,000 Hz
Sound waves are which type of wave?
Longitudinal
Define the variables in the wave speed formula include units.
v = wave speed m/s
f = frequency Hz
λ = wavelength m
Order the material/meidum in which sound travels from slowest to fastest:
Gas Slowest
Liquids
Solids Fastest
What is it called when waves overlap?
Interference
What causes a wave to bend?
Refraction
Sound waves must travel through a
Medium/Material
A sound wave travels at 423 m/s and has a frequency of 789 Hz, what is the wavelength? Write the formula, show work, round to two decimal places and use correct units.
λ = v/f
λ = 423/789
λ = 0.54 m
Sound waves are able to bounce or reflect off a surface which is known as an
Echo
Which type of interference produces a louder sound? Which two parts of the wave are meeting?
Which type of wave property determines pitch? Describe the relationship
Frequency, directly proportional
High frequency = high pitch
Low frequency = low pitch
What is the speed of sound in air and in water?
Air: 343 m/s
Water: 1500 m/s
A person shouts and hears an echo 5.2 seconds later, how far away is the reflecting surface? Write the formula, show work, round to a whole number and use correct units.
d = vt/2
d= (343)(5.2)/2
d = 892 m
What is the formula for echo distance? What is each variable?
d = vt/2
d = distance
v = wave speed
t = time
In the Doppler Effect what is changing due to motion? Describe the motion
Frequency
Sound is higher as it approaches
Sound is lower as it moves away
Which type of wave property determines loudness?
Amplitude
What is the human hearing range?
20 Hz - 20,000 Hz
A tuning fork produces a sound with a wavelength of 2.3 m in water. What is the frequency? Write the formula, show work, round to a whole number and use correct units.
f = v/λ
f = 1500/2.3
f = 652 Hz
Explain what happens to sound when it moves from cooler air to warmer air
Sound speeds up in the warmer air
What is volume measured in?
Decibels
Which diffracts less, high-frequency or low-frequency
High-frequency