Taw qhia rau kev yoj sawv
Ib nthwv dej sawv yog lub xeev txoj kev xa khoom raws txoj kev xa khoom los ntawm ob nthwv dej ntawm tib lub zog thiab cov lus qhia sib luag ntawm kev xa mus (tsis tas yuav siv hluav taws xob). Ib ntawm nthwv dej feem ntau pom nthwv dej ntawm lwm nthwv dej. Ib qho antinode tshwm ntawm qhov chaw qhov hluav taws xob (lossis qhov tam sim no) ntxiv, thiab ib qho ntawm node raug tsim rau ntawm qhov chaw uas qhov hluav taws xob (lossis tam sim no) rho tawm. Ntawm kev tawm suab, txoj haujlwm ntawm cov nodes thiab antinodes yeej ib txwm ua tas li, muab qhov pom ntawm "sawv twj ywm", tab sis nws tus nqi tam sim hloov nrog lub sijhawm. Yog hais tias qhov ntau ntawm ob qhov kev sib txig sib luag, qhov sib cuam tshuam ntawm cov ntshav yog xoom.