Penjelasan yang bahkan saya masih tetap tak mengerti meskipun membacanya berkali-kali bisa kamu lihat di bawah. Maaf, terlalu lieur untuk diterjemahkan.
Imagine a trampoline. The center moves a ton but the edges are fixed. The non-moving part of is called a node and the moving part an antinode. The powder falls down into the nodes because they are the areas where there is least movement. At a certain frequency the nodes are extremely defined and that's a resonating frequency of the pate. The patterns change with frequency because the pate vibrates differently with different frequencies.