Answer:
<em>λ </em>= 0.28m
Explanation:
Equation used is <em>v = λf</em>, where <em>v</em> is velocity, <em>λ</em> is wavelength, and <em>f</em> is frequency
We need to find wavelength so rearrange the equation in term of wavelength.
<em>v = λf</em>
<em>λ = f/v</em>
We know that period is the inverse of frequency (f = 1/T), so lets substitute that into our equation
<em>λ = f/v</em>
<em>λ = (1/T)/v</em>
Plug in your the given values given in the question.
We're given v=12m/s and T=3sec
<em>λ = (1/T)/v</em>
<em>λ</em> = (1/3)/12
<em>λ</em> = 1/36 = 0.2777777 = 0.28m