Question

the position of a particle of matter in the absence of a wave is called the a normal location. b resting position. c midline. d trough

Explanation:

To solve this, we analyze each option:

• Option a: "normal location" is not the standard term for a particle's position without a wave.
• Option b: In wave physics, the position of a matter particle when there's no wave (i.e., when it's not disturbed by the wave) is called the resting position. This is a key concept in understanding wave - particle interactions.
• Option c: "midline" is more of a general term for a central line and not specific to the particle's position in the absence of a wave.
• Option d: A "trough" is a low - point of a wave, not the position of the particle when there's no wave.

Answer:

b. resting position