Answer :
The time taken for the wave to travel 3000 cm is 2.4 seconds.
What is wavelength?
This is a distance in line of a progressive wave, from one point to another.
Distance of one wavelength
The distance of a half wavelength (high point to the low point) is given as 5 cm.
[tex]\frac{1}{2} \lambda = 5\ cm\\\\\lambda = 2(5 \ cm) = 10 \ cm = 0.1 \ m[/tex]
Speed of the wave
The speed of the wave is calculated as follows;
[tex]v = f \lambda\\\\v = 125 \times 0.1\\\\v = 12.5 \ m/s[/tex]
Time to travel 3000 cm
The time taken for the wave to travel 3000 cm is calculated as follows;
[tex]t = \frac{d}{v} \\\\t = \frac{30 \ m}{12.5 \ m/s} \\\\t = 2.4 \ s[/tex]
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