Waves are generated on a water surface. Calculated the phase difference between two points A and B, when
(i) A and B lie on the same wave front at a distance `=2lambda` between them.
(ii) A and B lie on successive crests separated by 1 metre.
(iii) A and B lie on successive troughs separated by 1.5m

Explanation

(i) On the same wave front , phase diff. `=0`. Linear distance between the points does not matter.
(ii) Between two successive crests, path diff. `=lambda`
`:. `phase diff. `=2pi` radian.
(iii) Again, path difference between two successive troughs `=lambda`
`:. ` phase diff. between A and B `=2pi` radian