Question

A plane wave is described by the equation

$y = 3\cos\left( \frac{x}{4} - 10t - \frac{\pi}{2} \right)$. The maximum velocity of the particles of the medium due to this wave is

• A. 30
• B. 3$\pi/2$
• C. 3/4
• D. 40

Answer 1

Answer: (A)

30

Answer 2

Maximum velocity = A$\omega$ = 3 × 10 = 30