Confusion over gravity and tides

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Discussion Overview

The discussion revolves around the relationship between the Moon's gravity and the Earth's gravity, specifically how the Moon's gravitational influence can create tides despite its weaker pull. Participants explore concepts related to gravitational forces, the nature of gravity, and the mechanics of tidal movements.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • One participant expresses confusion about how the Moon's weaker gravity can still affect tides on Earth.
  • Another participant suggests that the tides are caused by the difference in gravitational forces, noting that while the Earth's gravity is stronger, it is uniform across the oceans, allowing the Moon's influence to create an imbalance.
  • A participant questions the nature of gravity, asking if it travels in waves and whether these waves could cancel out the Moon's gravitational effect before reaching Earth.
  • Another participant clarifies that gravity is not transmitted by waves, although gravity waves exist, they do not function in the same way as gravitational pull.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the nature of gravity and its transmission. There are competing views regarding the mechanics of tidal forces and the concept of gravity waves.

Contextual Notes

The discussion includes assumptions about gravitational forces and their effects, as well as the nature of gravity waves, which remain unresolved. The relationship between the Moon's and Earth's gravitational influences is also not fully clarified.

chis
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I am having trouble rationalising the fact that the moons gravity is a fraction of the Earth's and is far out in space, but still manages to out pull the Earth's gravity albeit a tiny amount and create tides?
 
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One thing that might help is to recall that the tides are caused only by the difference between forces. It's true that the Earth's gravitational field has much more pull on the seas than the Moon's. But, the Earth's pull on the sea is pretty much the same all over. So, the oceans all over the Earth "feel" the Earth's gravitational pull about equally; like a perfectly ballanced system. The tiny influence of the Moon is then enough to upset that ballance.
 
Thanks guys, is the assumption that gravity travels in waves and if so is there evidence of reinforcement or canellation. Hence my original question should the opposing gravity waves result in the Moons being totally canceled out before reaching Earth.
 
chis said:
Thanks guys, is the assumption that gravity travels in waves and if so is there evidence of reinforcement or canellation. Hence my original question should the opposing gravity waves result in the Moons being totally canceled out before reaching Earth.

The force of gravity is not carried by waves. There are gravity waves, but they have the same relationship to the pull of gravity as light has to the pull of a magnet.
 

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