Question

The equation of stationary wave is

y = 4sin $\left( \frac{\pi x}{15} \right)$cos (96pt). The distance between a node and its next antinode is –

• A. 7.5 units
• B. 1.5 units
• C. 22.5 units
• D. 30 units

Answer 1

Answer: (A)

7.5 units

Answer 2

y = 4 sin $\left( \frac{\pi x}{15} \right)$cos (96pt) ….(1)

y = 2a sin kx cos wt ….(2)

from comparison 1 & 2

k = $\frac{\pi}{15}$ = $\frac{2\pi}{\lambda}$

l = 30

Distance b/w nearest node and Antinode = l/4

= $\frac{30}{4}$= 7.5 unit