Which of the following is an example of a longitudinal wave?

• A. Light waves traveling through vacuum
• B. Waves on a stretched guitar string
• C. Sound waves traveling through air
• D. Ripples on the surface of a pond

Answer: (C)

Verified step by step guidance

1. Understand the difference between longitudinal and transverse waves: In longitudinal waves, the particle displacement is parallel to the direction of wave propagation, while in transverse waves, the displacement is perpendicular to the direction of wave propagation.
2. Analyze each option: Light waves traveling through vacuum are electromagnetic waves and are transverse in nature because their electric and magnetic fields oscillate perpendicular to the direction of propagation.
3. Waves on a stretched guitar string are transverse waves because the string vibrates up and down (perpendicular) while the wave travels along the string.
4. Sound waves traveling through air are longitudinal waves because air particles oscillate back and forth in the same direction as the wave travels, creating compressions and rarefactions.
5. Ripples on the surface of a pond are transverse waves because the water surface moves up and down perpendicular to the direction the wave travels.