the displacement y of a particle in a medium can be expressed as
y = `10^(-6) sin (100 t + 20 x + (pi)/(4) ) ` m where t is in seconds and x in metre
The speed of wave is :

Options

A. 2000 m/s
B. 50 m/s
C. 20 m/s
D. 5 m/s

Answer

D

Explanation

`y = 10^(-6) sin (100 t + 20 x + pi//4).`
comparing it with standard form y = r sin `(omega t + kx + phi ) `
`omega = 100 s^(-1) and k = 20 `
`therefore v = (omega)/(k) = 5 ms^(-1)`
correct choice is (d).