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### Course: Physics library>Unit 18

Lesson 3: Measuring magnetic fields

# Force over distance

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?

## Want to join the conversation?

• How come the magnet did not effect the compass when it was like 4 inches away?
• Because Earth's magnetic field is stronger than magnet's magnetic field at that distance.
(1 vote)
• 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.
• 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.
• What is magnetisom why is it in a magnet?
• 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.
(1 vote)
• 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.
• what are all of does objects ? and what do they do ?
• What is the picture shown?