Correct statement about sound wave

[songoku]

Homework Statement

Please see below

Relevant Equations

None

My answer is (1) and (2) but the teacher said it is only (1). I thought the speed of point at center of compression and center of rarefaction would be the maximum.

Or the correct one is the speed at center of compression and center of rarefaction would be zero?

Thanks

 

[Orodruin]

Your teacher is wrong. Each particle is undergoing SHM and so velocity is the greatest whenever displacement is zero.

 

[songoku]

Thank you very much Orodruin