A wave travelling on a string at a speed of 10 m s − 1 causes each particle of the string to oscillate with a time period of 20 ms. (A) What is the wavelength of the wave? (B) If the displacement of a particle is 1 5 mm at a certain instant, what will be the displacement of a particle 10 cm away from it at the same instant?

Question

Philoid · Accepted Answer

A. 20 cm

The speed of the wave is given by,

B. − 15 mm

Here we are finding the displacement at distance of λ/2.

The phase difference will be,

This shows that they are going to be in opposite phase.

So, the displacement will be -1.5mm.