### Waves - Result Question 21

#### 21. The equation of a sound wave is given as: $y=0.0015 \sin (62.4 x+316 t)$. The wavelength of this wave is

[1996]

(a) 0.4 unit

(b) 0.3 unit

(c) 0.2 unit

(d) 0.1 unit

## Show Answer

#### Answer:

Correct Answer: 21. (d)

Solution:

- (d) $y=0.0015 \sin (62.4 x+316 t)$

On comparing with $y=A \sin (\omega t+k x)$

$\omega=316, k=62.4$

$\Rightarrow k=\frac{2 \pi}{\lambda}=62.4 \Rightarrow \lambda=0.1$ unit