# Chapter 21 - Superposition - Conceptual Questions - Page 620: 3

(a) The mode is 2 (b) The air molecules are moving horizontally. (c) The air molecules oscillate with maximum amplitude at the positions 0 cm, 16 cm, and 32 cm from the left end of the tube. (d) The air pressure oscillates with maximum amplitude at the positions 8 cm and 24 cm from the left end of the tube.

#### Work Step by Step

(a) The figure shows a standing wave with two nodes. Thus the mode is 2. (b) The air molecules are moving horizontally. As the wave travels through the tube, the air molecules are alternately squeezed horizontally and expanded horizontally. (c) The antinodes in the figure show the points where the air molecules oscillate with maximum amplitude. These antinodes are at the positions 0, 16 cm, and 32 cm from the left end of the tube. (d) The nodes in the figure show the positions where the air pressure oscillates with maximum amplitude. The nodes are at the positions 8 cm and 24 cm from the left end of the tube.

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.