Rarefaction of the crystal results in:

Rarefaction of the crystal results in:

• A. Low particle density
• B. High particle density
• C. No change
• D. Increased temperature

Answer: (A)

Rarefaction is the part of a wave where particles move apart, so the local density drops. In a crystal, as the sound wave passes, the atoms oscillate and the spacing between them increases during rarefaction, leading to fewer particles per unit volume. This is the opposite of compression, where atoms are pressed closer together and density rises. Temperature changes aren’t the defining feature here in the simple wave picture, so the hallmark outcome is low particle density.

Rarefaction is the part of a wave where particles move apart, so the local density drops. In a crystal, as the sound wave passes, the atoms oscillate and the spacing between them increases during rarefaction, leading to fewer particles per unit volume. This is the opposite of compression, where atoms are pressed closer together and density rises. Temperature changes aren’t the defining feature here in the simple wave picture, so the hallmark outcome is low particle density.