4 What is a good definition of a TIDE? The periodic rise and fall of the water level in the oceans
5 What are causes of tides? Largest force = the gravitational forces from both the sun and the moonOther forces:WindEarthquakesPlate tectonics
6 Sir Isaac Newton to the Rescue! Newton’s Universal Gravitation Theory helped to explain how the gravity of the moon (and the sun) were related to tides.
7 The moon’s gravity pulls on everything on the Earth The pull on liquids is more noticeable than on solids because liquids move more easily than solids
8 The moon’s pull is strongest on the part of the Earth directly facing the moon
9 Earth’s rotation through tidal bulges causes most coastlines to experience two high tides and two low tides every 25 hours.
10 High TideThe part of the ocean directly facing the moon bulges toward the moonThere is a bulge on the opposite side because the water farthest from the moon is pulled toward the moon less strongly than are other parts of Earth
11 Low Tide The places between the bulges of the high tide High tide bulges take water away from low tide areas
12 Spring TideDuring a full moon and new moon (when the sun, earth, and moon are fully lined up) is the greatest difference between the heights of the high and low tidesHighest high tide and lowest low tide
13 Neap TideDuring the First Quarter and Third Quarter phases of the moon, the low and high tide do not have much of a difference from one another
14 Which is the Spring Tide, and which is the Neap Tide?