Question

the type of wave that eli creates in the spring toy is called a longitudinal wave. unlike a transverse wave, a longitudinal wave travels in a direction that is parallel to the direction the particles in the medium move. when eli moves his hand back and forth, the coils in the spring toy squeeze together and pull apart horizontally. a wave of compressing and stretching then travels along the horizontal length of the spring toy. what is true about the longitudinal wave that eli creates in the spring toy? select the true sentences. the waves and the particles of matter move in parallel directions. the particles of matter in the spring toy move up and down. the waves and the particles of matter move in perpendicular directions. the wave travels from left to right.

Explanation:

The problem is about the properties of a longitudinal wave. According to the text, a longitudinal wave travels in a direction parallel to the direction of particle movement. In the case of the spring toy, when Eli moves his hand back and forth (horizontal - left - right direction), the coils (particles) move horizontally (back and forth), and the wave (compression and stretching) also travels horizontally (left - right).

1. For the first option: The text states "a longitudinal wave travels in a direction that is parallel to the direction the particles in the medium move", so this option is correct.
2. For the second option: The particles move back and forth (horizontal direction), not up and down. So this option is incorrect.
3. For the third option: Since the wave and particle movement directions are parallel (not perpendicular), this option is incorrect.
4. For the fourth option: When Eli moves his hand back and forth, the wave (compression and stretching) travels along the horizontal length (left - right) of the spring toy. So this option is correct.

Answer:

The waves and the particles of matter move in parallel directions; The wave travels from left to right.