That's question 18 solve it in English

Here's the solution for Question 18: Question 18: Problem Statement: What is the phase difference between two points 0.16 \, m apart on a progressive sound wave of frequency 256 \, Hz given that the speed of sound is 330 \, m/s? Step 1: Calculate the wavelength () of the sound wave. The relationship between wave speed (v), frequency (f), and wavelength () is given by the formula: v = f We need to find , so we rearrange the formula: = (v)/(f) Substitute the given values: v = 330 \, m/s and f = 256 \, Hz. = 330 \, m/s256 \, Hz ≈ 1.2890625 \, m Step 2: Calculate the phase difference ( ). The phase difference ( ) between two points separated by a distance x on a progressive wave is given by the formula: = (2)/() x Substitute the calculated wavelength and the given distance x = 0.16 \, m: = (2)/(1.2890625 \, m) (0.16 \, m) = 2 × (0.16)/(1.2890625) ≈ 2 × 0.12412 ≈ 0.24824 \, rad This value is very close to 0.25, which is ()/(4). To be more precise, let's express the ratio ( x)/() as a fraction: ( x)/() = (0.16)/(330/256) = (0.16 × 256)/(330) = (40.96)/(330) This fraction is approximately 0.12412. If we consider the options, ()/(4) corresponds to a ratio of (1)/(8) = 0.125. The calculated value is very close to this. The final answer is C. Drop the next question.