## If the moon was twice as far away from the earth as it actually is, how would tides b

"If the moon was twice as far away from the earth as it actually is, how would tides be effected?"

Thanks!

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 Tides would reduce, i'm thinking.

Mentor
 Quote by vincentm Tides would reduce, i'm thinking.
I think you're correct.

Kay, what sort of answer are you looking for? Will "they will reduce" suffice, or are you looking for more of an quantitative explanation?

## If the moon was twice as far away from the earth as it actually is, how would tides b

Cristo, I am definately looking for an answer that provides some meaning. This is part of a homework assignment and I am stumped!

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 Quote by kay89 Cristo, I am definately looking for an answer that provides some meaning. This is part of a homework assignment and I am stumped!
If its homework related we kindly request that you show your attempt at this question before receiving any help.

 2 squared is = to 4

Mentor
 Quote by ray b 2 squared is = to 4
That's fine, but the tides do not vary with the square (or even the inverse square) of distance.

 Mentor To help answer both the OP and explain my response to ray b, consider the Sun. The Sun is 27 million times more massive than is the Moon and is about 389 further times distant from the Earth than is the Moon. Yet the tidal forces caused by the Sun are slightly less than half those caused by the Moon.
 a quick google shows gravity along with alot of other stuff works on inverse square which is what the hint was aimed at true thats for a point and tides are complex with many factors but that should be close to the correct answer

 Quote by ray b a quick google shows gravity along with alot of other stuff works on inverse square which is what the hint was aimed at true thats for a point and tides are complex with many factors but that should be close to the correct answer
No. Try it for the sun.

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 Quote by ray b a quick google shows gravity along with alot of other stuff works on inverse square which is what the hint was aimed at true thats for a point and tides are complex with many factors but that should be close to the correct answer
Not anywhere close to the correct answer. Look at the numbers from my previous post: The Sun is 27 million times more massive than is the Moon and is about 389 further times distant from the Earth than is the Moon. If tidal effects were indeed an inverse square relationship, solar tides would be 178 times larger than lunar tides. This is not the case. Solar tides are less than half the size of lunar tides. Tidal effects are not an inverse square relationship.

 the tide would reduce by half, as it is twice the difference away :D