Explain the following statement-

‘In a standing wave, all particles of the medium cross the mean position with different speeds at same instant.’

In a standing wave the particles perform oscillations across mean position just as you stretch a thread or string and pluck it in the midpoint or any other point The particles start oscillating vertically to and fro across the mean position which was the position when the string or thread was at rest To produce such a standing wave the particles will anyway have to reach the mean position together and for they`ll possess different speeds as they are at different highest positions If you understand the concept practically you`ll get it|

In standing wave i.e a stationary wave all particle have different amplitude so all have different velocity but they all reach their extreme position simultaneously