Practice Longitudinal Wave in Physics
Use these practice problems to test your method after reviewing the concept explanation and worked examples.
Quick Recap
A wave where the medium oscillates parallel to the direction of wave travel, forming compressions and rarefactions.
A slinky pushed back and forth: compressions and stretches travel along it.
Example 1
easyA longitudinal wave in a spring has compressions 0.4 \text{ m} apart. The wave frequency is 5 \text{ Hz}. What is the wave speed?
Example 2
mediumSound travels at 340 \text{ m/s} in air and 5100 \text{ m/s} in steel. A 1000 \text{ Hz} sound wave enters a steel rail. What is the wavelength in each medium?
Example 3
mediumAn ultrasound device emits sound at 2 \times 10^6 \text{ Hz} in human tissue (v = 1540 \text{ m/s}). What is the wavelength? Why is this frequency useful for medical imaging?
Example 4
hardAn earthquake produces both P-waves (v_P = 6000 \text{ m/s}, longitudinal) and S-waves (v_S = 3500 \text{ m/s}, transverse). A seismograph detects the P-wave 20 \text{ s} before the S-wave. How far away is the earthquake?