Answer:
Which of the following is NOT TRUE about a longitudinal wave?
- A. They are all considered mechanical waves.
- B. They need a medium (material) in order to travel.
- C. They move up and down (perpendicular) to the direction of the wave's energy.
- D. They move along with (parallel to) the direction of the wave's energy.
Step-by-step explanation:
What are waves?
- A wave is a disturbance in a medium that carries energy without permanently moving a substance. Particles of the medium are momentarily displaced and then return to their original location in a wave.
- Mechanical waves are waves that require a medium to transport energy from one location to another.
- Mediums are materials that move energy or light from one substance or location to another.
Answer breakdowns
- Choice C is the best answer. In a transverse wave, particles of the medium are displaced in a direction that is perpendicular to the direction of energy transport.
- Choice D is incorrect. This choice describes exactly what a longitudinal wave is. In a longitudinal wave, particles of the medium are displaced in a direction that is parallel to the direction of the wave's energy.
- Choice A is incorrect. A mechanical wave is any wave that requires a medium to transport energy from one location to another.
- Choice B is incorrect. As per choice A's explanation, if the longitudinal waves are mechanical they must then require a medium.