Question

Trina performed an experiment in which she created different types of waves and sent them through various media. The movement of the particles in the wave and the behavior of the wave as it moved from air into each medium was recorded in a table.

Wave Movement of Particles Behavior in Medium A Behavior in Material B
1 right and left slowed down sped up
2 front and back sped up no motion
3 front and back sped up no motion
4 front and back sped up no motion
5 right and left slowed down sped up

Which of the following is correct about Trina's experiment?
A.
Material B must have been a vacuum because mechanical waves like 2, 3, and 4 cannot propagate in a vacuum.


B.
Material B must have been denser than air because the electromagnetic waves, 2, 3, and 4, stopped moving.


C.
Material A must have been a vacuum because electromagnetic waves like 1 and 5 move the fastest in a vacuum.


D.
Material A must have been denser than air because the mechanical waves, 1 and 5, slowed down.

Answer 1

Let's analyze the information provided and the options given.

1. The movement of the waves and their behavior as they moved into different media suggest that there are two types of waves involved:
- **Mechanical Waves** (e.g., waves 1 and 5 with right and left movement, and waves 2, 3, and 4 with front and back movement).
- **Electromagnetic Waves** (assuming waves 2, 3, and 4 are electromagnetic based on their behavior).

Additionally, we consider how waves behave when they move from a less dense medium (like air) to a denser medium:
- **Mechanical Waves:** Generally slow down when entering a denser medium.
- **Electromagnetic Waves:** Generally speed up when entering a denser medium (except when entering a material that is denser than the previous medium).

Now, let's evaluate each option:

**A. Material B must have been a vacuum because mechanical waves like 2, 3, and 4 cannot propagate in a vacuum.**
- Incorrect. Mechanical waves cannot propagate in a vacuum, but whether Material B is a vacuum is not determined here.

**B. Material B must have been denser than air because the electromagnetic waves, 2, 3, and 4, stopped moving.**
- Incorrect. The waves did not "stop moving"; they exhibited "no motion," which suggests the medium may not support their propagation.

**C. Material A must have been a vacuum because electromagnetic waves like 1 and 5 move the fastest in a vacuum.**
- Incorrect. While electromagnetic waves do move fastest in a vacuum, there's no support in the provided data that indicates that Material A is a vacuum based on the wave behavior.

**D. Material A must have been denser than air because the mechanical waves, 1 and 5, slowed down.**
- Correct. The mechanical waves slowing down as they entered Material A indicates that it is likely denser than air.

Thus, the correct answer is **D. Material A must have been denser than air because the mechanical waves, 1 and 5, slowed down.**