Force of magnet m= Strength of magnet M/Distance from the affected object Is my equation correct?

In 3 dimensional space the strength of fields like magnetism and gravity decrease with the square of the distance so if you double the distance you decrease the strength by 4 times.

Does anyone know why earths magnetic field went berserk at the exact same time the each WTC tower fell to the ground?

Do you have a citation for that? Sounds like BS to me.

if there is a giant strong magnet bigger than the earth, will the earth move?

good question... I guess it would feel a force. But the magnetic field of the Earth is relatively weak. It is strong enough to change the direction of charged particle coming from the Sun and outer space but i think the force due to another big magnet would be fairly small. Also, consider that the Sun also has magnet fields which are fairly strong. Any thoughts??

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Physics library

Course: Physics library > Unit 18

Lesson 3: Measuring magnetic fields

Force over distance

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Can you think of an experiment that would let you see how magnetic force depends on distance?

How does force change over distance?

We have noticed that the force of a magnet seems to depend on our distance from it.

Can you think of an experiment which would describe a magnet's force across a distance?

Is the relationship linear?

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William Kilpatrick
Posted 8 years ago. Direct link to William Kilpatrick's post “How come the magnet did n...”
How come the magnet did not effect the compass when it was like 4 inches away?
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(5 votes)
Answer
- ritik bhardwaj
  Posted 2 years ago. Direct link to ritik bhardwaj's post “Because Earth's magnetic ...”
  Because Earth's magnetic field is stronger than magnet's magnetic field at that distance.
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  (1 vote)
Varun
Posted 10 years ago. Direct link to Varun's post “Maybe you can have a comp...”
Maybe you can have a compass oriented vertically rather than horizontally. Then, depending on how close the magnet was, the needle will tilt less or more toward the magnet.
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(5 votes)
Answer
raineeee
Posted 7 years ago. Direct link to raineeee's post “Force of magnet m= Streng...”
Force of magnet m= Strength of magnet M/Distance from the affected object
Is my equation correct?
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(2 votes)
Answer
- Charles LaCour
  Posted 7 years ago. Direct link to Charles LaCour's post “In 3 dimensional space th...”
  In 3 dimensional space the strength of fields like magnetism and gravity decrease with the square of the distance so if you double the distance you decrease the strength by 4 times.
  Comment on Charles LaCour's post “In 3 dimensional space th...”
  (4 votes)
Kaitlyn likes fries
Posted 8 years ago. Direct link to Kaitlyn likes fries's post “What is magnetisom why is...”
What is magnetisom why is it in a magnet?
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(3 votes)
Answer
- ritik bhardwaj
  Posted 2 years ago. Direct link to ritik bhardwaj's post “There are different type ...”
  There are different type of materials according to their magnetic properties which are causes due to spin of electron and nucleus. Ferromagnetic materials (permanent magnets) are one of those materials in which spins of electrons are in same direction which causes magnetism.
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  (1 vote)
jc99612510
Posted 8 years ago. Direct link to jc99612510's post “what are all of does obje...”
what are all of does objects ? and what do they do ?
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(3 votes)
Answer
Rick McCall
Posted 6 years ago. Direct link to Rick McCall's post “Does anyone know why eart...”
Does anyone know why earths magnetic field went berserk at the exact same time the each WTC tower fell to the ground?
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(2 votes)
Answer
- Andrew M
  Posted 6 years ago. Direct link to Andrew M's post “Do you have a citation fo...”
  Do you have a citation for that? Sounds like BS to me.
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  (2 votes)
paturutanmay
Posted 7 years ago. Direct link to paturutanmay's post “What is the picture shown...”
What is the picture shown?
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(2 votes)
Answer
ASach14
Posted 8 years ago. Direct link to ASach14's post “can they make a video abo...”
can they make a video about this?
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(2 votes)
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Chanel Pien
Posted 7 years ago. Direct link to Chanel Pien's post “What is the distance betw...”
What is the distance between Earth and the magnet??
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(2 votes)
Answer
Younglan Oh
Posted 6 years ago. Direct link to Younglan Oh's post “if there is a giant stron...”
if there is a giant strong magnet bigger than the earth, will the earth move?
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(1 vote)
Answer
- Teacher Mackenzie (UK)
  Posted 6 years ago. Direct link to Teacher Mackenzie (UK)'s post “good question... I guess ...”
  good question... I guess it would feel a force. But the magnetic field of the Earth is relatively weak. It is strong enough to change the direction of charged particle coming from the Sun and outer space but i think the force due to another big magnet would be fairly small.
  
  Also, consider that the Sun also has magnet fields which are fairly strong.
  
  Any thoughts??
  Comment on Teacher Mackenzie (UK)'s post “good question... I guess ...”
  (3 votes)