A wave with frequency $15\,\text{Hz}$ moves through a medium at $24\,\text{m s}^{-1}$. What phase difference is there between two points separated by $2.0\,\text{m}$?
- AThere is no phase difference.
- BThey are out of phase by a quarter of a cycle.
- CThey are out of phase by half a cycle.
- DThey are out of phase by $0.80$ of a cycle.