Since the waVe equation of a travelling wave:- 
Let 
( : : It is travelling in opposite direction)
By principle of superposition, wave equation for the resultant wave 
![\[\begin{array}{l} y=a \operatorname{Sin} 2 \pi\left(\frac{t}{T}-\frac{x}{\pi}\right)+\mathrm{a} \operatorname{Sin} 2 \pi\left(\frac{t}{T}+\frac{x}{\pi}\right) \\ =a\left(\operatorname{Sin} 2 \pi\left(\frac{t}{T}-\frac{x}{\pi}\right)+\mathrm{a} \operatorname{Sin} 2 \pi\left(\frac{t}{T}+\frac{x}{\pi}\right)\right) \\ \text { Using } \operatorname{Sin} \mathrm{C}+\operatorname{Sin} \mathrm{D}=\mathrm{a} \operatorname{Cos} \frac{C-D}{z} \cdot \frac{\operatorname{Sin} C+D}{z} \\ y=2 a \operatorname{Cos} \frac{2 \pi x}{\pi} \cdot \frac{\operatorname{Sin} 2 \pi \mathrm{t}}{T} \end{array}\]](https://www.learnatnoon.com/s/wp-content/ql-cache/quicklatex.com-31f8d593a97c8b8fe005bb0e87828118_l3.png "Rendered by QuickLaTeX.com")
Here 
![\[\begin{array}{l} T=\frac{1}{30} \mathrm{sec}, \pi=\text { wavelength }=\frac{v}{f}=V T \\ \pi=180 \times \frac{1}{30}=6 \mathrm{~cm} \end{array}\]](https://www.learnatnoon.com/s/wp-content/ql-cache/quicklatex.com-7643cde32e18d792f9961439ff87924b_l3.png "Rendered by QuickLaTeX.com")
The amplitude, frequency and velocity of the component waves producing a stationary wave are 
