Question

a source produce 15 waves in 3 sec . The
distance between a crest and Trough in 15cm.
Find the frequency, wave length and
velocity the wave​

Answer 1

$\Huge{\underline{\underline{\blue{\mathfrak{Solution :-}}}}}$

$\sf {Number\ of\ waves\ produced\ in\ one\ second\ is\ \frac{15}{3} = 5\ waves}$

So the frequency is 5 Hz

Given

$\sf {Wave\ length\ \frac{\lambda}{2}=10\ cm}$

$\sf {Therefore\ \lambda = 20\ cm}\\\\\sf {Speed\ v = \nu \lambda = Frequency \times wave length}\\\\ \sf {v = 5 \times 20}\\\\ \sf {v = 100\ m/s}$