Presentation on theme: "Tides Tides and the Moon. It’s the Difference… …in Gravity Gravity obeys the inverse square law. so The Moon’s gravity pulls harder on the water on the."— Presentation transcript:
It’s the Difference… …in Gravity Gravity obeys the inverse square law. so The Moon’s gravity pulls harder on the water on the near side of the Earth than it does on the Earth. This pulls the water on the near side away from the Earth… making a High Tide on the near side. The Moon’s gravity pulls harder on the Earth than it does on the water on the far side of the Earth. This pulls the Earth away from the water on the far side… making a High Tide on the far side
Low Tides Low Tides occur on the sides of the Earth neither facing nor away from the Moon. There the Moon pulls on the Earth and Water the same. High Tides High Tides Occur on the sides of the Earth either facing toward or directly away from the Moon On the near side the Moon pulls the Water away from the Earth On the far side the Earth is pulled away from the water
The Sun and Tides The Sun also causes Tides, These Tides are much weaker than those from the Moon because difference in the gravity is less Since the Earth is so small compared to the distance to the Sun. Even though the Sun pulls on Earth with more force than the Moon does. The Sun’s Tides affect Moon’s tide changes by adding to or subtracting from them.
Spring and Neap Tides When the Moon is New or Full the Sun, Earth and Moon Line up and Sun and Moon Tides work together. The High tide is the highest and the Low tide is lowest… Spring Tides When it’s a First or Last Quarter Moon the Sun, Earth and Moon form a right angle and the Sun’s tides cancel some of the Moon’s stronger tides. The High Tide isn’t very high and the Low Tide isn’t so low… Neap Tides
The Timing of the Tides The Tide at a point on Earth should be highest when that point is nearest...or farthest from the Moon. That is when the moon is at its highest altitude…. and it’s lowest What time this is depends on the phase of the Moon. For example: When the Moon is full it reaches its highest altitude at midnight, so that should be High Tide. The Exact time is affected by a delay due to the friction with the Earth, and local geography.
Tidal Braking The Earth Spins faster than the Moon Moves West to East. The friction between the Water and the Solid Earth drags the Tidal Bulge forward The Tidal Bulge will pull the Earth backward and makes the Earth Spin slower… Tidal Braking. Each Century a day gets about.00164 seconds longer! (That’s 16.4 sec every million years) The Tidal Bulge pulls back on the Moon making: It speed up, moving it away from Earth Its revolution and rotation Synchronous