My question is quite a simple one, but one that is confusing me quite a bit. I was think why a ship needs an anchor? This sounds silly but this is why I ask. When you but a ball in the middled of water for example and you are a meter away and create waves in the water the ball just move up and down, it does not move. So basically the same principle as a transverse wave, where the medium through which the energy travels, is perpendicular to the wave direction. So surly the is no need for a anchor because the boat will not move, it will only bob up and down.