Q8 of 97 Page 323

The equation of a wave travelling on a string is

y = (010 mm) sin[(314 m−1) x+ (314 s−1) t].


(A) In which direction does the wave travel? (B) Find the wave speed, the wavelength and the frequency of the wave. (C) What is the maximum displacement and the maximum speed of a portion of the string?


A. negative x-direction


The structure of the equation is y = A sin(kx + ωt)


Comparing with y = A sin(ωt - kx) we find x є R-


B. 10 m s−1, 20 cm, 50 Hz


Wave speed





Wavelength,





Frequency





C. 0.10 mm, 3.14 cm s−1


Maximum displacement is the amplitude.


So, it will be, 0.10mm.


Now,



Now the maximum speed will be,




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