A wave in which the particles of the medium oscillate parallel to the direction of wave propagation, creating alternating regions of compression (high pressure) and rarefaction (low pressure).
A slinky pushed back and forth: compressions and stretches travel along it.
Showing a random 20 of 50 problems.
Example 1
easy
A sound wave has period 2 ms and travels at 340 m/s in air. Find its wavelength.
Example 2
medium
An ultrasound machine sends a 5 MHz longitudinal pulse into tissue (v≈1540 m/s). Find the wavelength.
Example 3
easy
A longitudinal wave in a spring has compressions 0.4 m apart. The wave frequency is 5 Hz. What is the wave speed?
Example 4
challenge
A sound wave at 1000 Hz enters a steel beam (v=5100 m/s). After traveling 20.4 m in the beam, how many full wavelengths fit, and what is the corresponding phase delay in radians?
Example 5
challenge
Sound (longitudinal) travels at 343 m/s in air and 1480 m/s in water at the same frequency 740 Hz. Find the wavelength in each and the ratio water-to-air.
Example 6
medium
A slinky longitudinal wave repeats its compression pattern every 0.2 s. Find its frequency and, if compressions are 0.3 m apart, the wave speed.
Example 7
easy
Can longitudinal waves be polarised?
Example 8
challenge
Show that a longitudinal wave's intensity drops as 1/r2 from a point source in 3D, by power-conservation reasoning.
Example 9
easy
Can longitudinal waves travel through solids and liquids, or only gases?
Example 10
medium
A longitudinal wave has frequency 5 Hz and wavelength 0.6 m. Find its speed.
Example 11
easy
Is sound a longitudinal or transverse wave?
Example 12
easy
In a longitudinal wave, the regions of low particle density are called ____.
Example 13
easy
Pushing and pulling a slinky along its length produces what type of wave?
Example 14
hard
Sound in air at 20°C is 343 m/s. The speed scales as T (in Kelvin). Find the sound speed at 0°C.
Example 15
easy
Longitudinal waves consist of which regions: crests and troughs, or compressions and rarefactions?
Example 16
medium
Why can't longitudinal waves be polarised?
Example 17
challenge
A longitudinal wave on a slinky has compressions 0.4 m apart and travels 8 m in 5 s. Find the speed, wavelength, and frequency.
Example 18
easy
Particles in a longitudinal wave oscillate in which direction relative to wave travel?
Example 19
challenge
A standing longitudinal wave in a pipe has nodes 0.4 m apart. The driving frequency is 425 Hz. Find the wave speed in the gas.
Example 20
medium
A pipe organ produces a sound at 440 Hz. Sound speed in air is 343 m/s. Find the wavelength.