Question

For the stationary wave $y = 4\sin\left( \frac{\pi x}{15} \right)\cos(96\pi t)$, the distance between a node and the next antinode is

• A. 7.5
• B. 15
• C. 22.5
• D. 30

Answer 1

Answer: (A)

7.5

Answer 2

Comparing given equation with standard equation

$y = 2a\sin\frac{2\pi x}{\lambda}\cos\frac{2\pi vt}{\lambda}$gives us $\frac{2\pi}{\lambda} = \frac{\pi}{15} \Rightarrow \lambda = 30$

Distance between nearest node and antinodes

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