Sound waves (node and antinodes)

[kelvin macks]

Homework Statement

for part a , since we know that the sand particles will vibrate will max amplitude at antinode and the displacement of partcles is 0 at node. then , the sand should heap at antinode . why the solution gives the sand heap at nodes?

Homework Equations

The Attempt at a Solution

 

[ehild]

The standing sound wave means that the air vibrates with high amplitude at the antinodes, and moves with high speed there. At the nodes, the air is in rest. The air flow takes the dust particles with itself, sets them into motion. It is like the broom sweeping dust or leaves. Watch video, especially from the 10th second. Where do the dust particles (leaves) accumulate? https://www.youtube.com/watch?v=iM_YIMC6Ic4

ehild

 

[kelvin macks]

The standing sound wave means that the air vibrates with high amplitude at the antinodes, and moves with high speed there. At the nodes, the air is in rest. The air flow takes the dust particles with itself, sets them into motion. It is like the broom sweeping dust or leaves. Watch video, especially from the 10th second. Where do the dust particles (leaves) accumulate? https://www.youtube.com/watch?v=iM_YIMC6Ic4

ehild

ok, can understand it finally.