Because when you throw a stone the molecules of water moves down in the vertical direction and then moves up to followed on. These ripples formed on the surface of water in pond are also transverse waves because in a water wave, the molecules of water move up and down in the vertical direction when the wave travels in horizontal direction along the water surface. These Ripples are the instant effect of stone on water and they die down as quickly as they form, as the surface tension of the water dampens their efforts.
A bottle filled with water is pierced in the side, so water flows out of the hole.
When a laser beam points from the opposite side through the hole, the beam is seen to travel along the water in a curved path, Why?
