How far does a wave travel in three cycles
?

60 nm

Explanation:

The wave equation applies:

where f = frequency

          λ = wavelength of the wave

In wave propagation, the wavelength represents one full wave cycle. This is the distance from one crest (peak) or trough (dip) to another crest (peak) or trough (dip). Therefore, a wave or say, 20 nm will have traveled after 3 cycles:

distance = 3 (20nm)

              = 60 nm

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explanation:

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