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DescriptionWaves in Box.svg
English: Standing electomagnetic waves in a box. Waves at the top have larger frequencies than those below and are shifted upward for clarity. At both boundaries the walls require nodes in the waves, so only waves with multiple half-wavelengths λ/2 fit in the box: λ/2 = W, λ = W, 3λ/2 = W where W = width of cavity.
Ελληνικά: Στάσιμο κύμα μέσα σε κουτί πλάτους W. Τα στάσιμα κύματα που σχηματίζονται έχουν μήκος κύματος ανάλογο του πλάτους του κουτιού. Τα κύματα έχουν αύξουσα συχνότητα από κάτω προς τα πάνω.
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{{Information |Description={{en|Standing electomagnetic waves in a box. Waves at the top have larger frequencies than those below and are shifted upward for clarity. At both boundaries the walls require nodes in the waves, so only wa