Question

A transverse progressive wave on a stretched string has a velocity of 10 m/s and a frequency of 100 Hz. The phase difference between two particles of the string which are 2.5 cm apart will be :

• A. $ \frac{\pi }{2} $
• B. $ \frac{3\pi }{8} $
• C. $ \pi /4 $
• D. $ \pi /8 $

Answer 1

Answer: (A)

$ \upsilon =n\lambda $ $ 10=100\lambda $ $ \Rightarrow $ $ \lambda =\frac{10}{100}=\frac{1}{10}m $ $ =10cm $ Phase difference $ =\frac{2\pi }{\lambda }\times $ path difference $ =\frac{2\pi }{10}\times 2.5=\frac{\pi }{2} $