Don't Panic Geocast

Tides pull and deform the surface of the ocean and the surface of the Earth. This week we’ll take a quick tour of tidal forces, address some show feedback, and then talk about a revision on a classic physics problem. Tides Tides are a result of gravitational interaction of the Sun-Earth-Moon system, but are of course a factor on many other planets as well. Gravity is the key to remember and that it varies linearly with mass, but with the inverse square of displacement. Ocean Tides The most familiar example is ocean tides. These are important for commerce, safety, and for sedimentary processes. Sedimentary layers called tidal rythmites Cool tide visualization from Calculated Images General cycle is a flood tide raises water levels until high tide. Then an ebb tide takes water back out until low tide is reached. When the tidal stream stops and reverses it is a slack tide. Generally occur with 24-hour or 12-hour period, can have a complex shape. Another kind of clock, a tide clock, has been made to show this.