Physics - Wave on String Question with Solution | TestHub

Mass per unit length $m=1.3\times 10^{-4}\mathrm{kg}/\mathrm{m}$ $y=0.021\sin (x+30t)$ Comparing with $y=a\sin \left(\omega t+\frac{2\pi x}{\lambda }\right)$ $a=0.021,\omega =30$ $2\pi n=30$ $\begin{array}{rl}& \Rightarrow n=\frac{30}{2\pi }\\ & \text{ We know that }\frac{2\pi }{\lambda }=1\\ & \end{array}$ $\begin{array}{rl}\therefore \lambda & =\frac{1}{2\pi }\\ \text{ Frequency, }n& =\frac{1}{\lambda }\sqrt{\frac{T}{m}}\\ \frac{30}{2\pi }& =\frac{1}{2\pi }\sqrt{\frac{T}{1.3\times 10^{-4}}}\\ T& =1.3\times 10^{-4}\times 900\\ & =0.117=0.12\mathrm{N}\end{array}$