do all particles in a wave have the same speed? they do right, else their frequency would be different, and frequency is only dependent on the freqeuncy of the source. but then again how can the speed of particles in a wave be the same , actually? logically speaking, a particle going up and coming down has different velocity, right? also, the wavelength decreases as the speed decreases in shallow water as compared to deep water. but why is this so? why does the speed and wavelength of a wave decrease in shallow water? Another question that's related: why is it that when we place a plastic sheet at an angle to incoming plane waves in ripple tank, and the water becomes shallow, that the change in speed of the waves will cause the waves to bend? all help will be greatly appreciated. and i would prefer to not have a mathematical outlook on the situation, as i've only learnt the basic wave formulas.