Question 271: Waves

Question

An observer on sea-coast counts 45 waves in one minute. If the wavelength of the waves is 7 m , then the velocity of the waves will be

Accepted Answer

Number of waves counted in 1 minute = 45
Time = 1 minute = 60 seconds
Therefore, frequency $(f)$ is:
$$ f = \frac{45}{60} = 0.75\, 	ext{Hz} $$
Wavelength $(\lambda) = 7\, 	ext{m}$
The velocity $v$ of the wave is given by the formula:
$$ v = f \lambda $$
Substituting the values:
$$ v = 0.75 	imes 7 = 5.25\, 	ext{m/s} $$
Correct option: B $5.25 \mathrm{~m} / \mathrm{s}$

Answer

$4.75 \mathrm{~m} / \mathrm{s}$

Answer

$5.25 \mathrm{~m} / \mathrm{s}$

Answer

$7.5 \mathrm{~m} / \mathrm{s}$

Answer

$8.65 \mathrm{~m} / \mathrm{s}$

Waves

An observer on sea-coast counts 45 waves in one minute. If the wavelength of the waves is 7 m , then the velocity of the waves will be

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