Physics

Problem

A progressive wave of frequency

20\,\text{Hz}

and wavelength

0.50\,\text{m}

travels along a rope. Two observations of the displacement at positions

A

and

B

are made

4.0\,\text{ms}

apart in time. What is the minimum distance between

A

and

B

so that the two observations are in phase? a)

0.25\,\text{m}

0.04\,\text{m}

0.50\,\text{m}

0.08\,\text{m}