Question

A plane progressive wave is given by $y=25\cos (2\pi t-\pi x)$ Then the amplitude and frequency are respectively

• A. 25, 100
• B. 25, 1
• C. 25, 2
• D. $50\pi ,2$

Answer 1

The correct option is B 25, 1

$\begin{array}{c}y=25\cos \left(2\pi f-\pi r\right)\\ A=25\\ w=2\pi =20t\\ \Rightarrow f=1\end{array}$

$\therefore$ option $B$ is correct.