No, two waves that have the same phase difference are not necessarily the same number of wavelengths apart.
The phase difference between two waves is a measure of the relative position of corresponding points on the waves. It indicates the fraction of a cycle or wavelength by which one wave leads or lags behind the other.
If two waves have the same phase difference, it means that corresponding points on the waves align with each other at the same position. However, this does not imply that the waves have the same number of complete wavelengths between them.
To illustrate this, consider two waves with the same phase difference of, for example, 0 radians or 0 degrees. At a specific point on one wave, the corresponding point on the other wave will also be at the same position. However, these points may not necessarily coincide at the same crest or trough of a wave. They could align at any point along the wave, including the crest, trough, or any intermediate position. Therefore, the number of wavelengths between these waves can vary.
The number of wavelengths between two waves depends on their frequency or period. If the frequencies or periods of the waves are the same, then the number of wavelengths between them would be the same. However, if the frequencies or periods differ, the number of wavelengths between them will also differ, even if they have the same phase difference.