Regarding the Earth's magnetic field

In summary, the lack of a magnetic field on Earth may be because it is too far away from the mag. field source, or the field is not powerful enough. There may be a way to harness the energy of the mag. field, but it is unknown at this time.
  • #1
baryon
35
0
Why doesn't the mag. field affect objects on Earth? Is it just too far away or not powerful enough or what? Also, is there any way to harness its energy other than moving a huge conductor though it? Wouldn't it have a frequency? Anyone know this?
 
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  • #2
Have you never used a magnetic compass? The magnetic field is relatively weak, so it isn't useful for much beyond that.
 
  • #3
I would say that the magnetic field does have quite an effect on compasses. It makes the needle point north and south.
 
  • #4
Correct. And there are far larger effects as in protecting us from extraterrestial charged particles that would otherwise render us incabable of living. In addition, although it doesn't really matter to me, there is very stong evidence to support the theory that birds (particularly homing pigeons) navigate by means of a ferrous membrane just above their beaks that allows them to follow magnetic field lines. That's something that Moonbear would probably be able to tune you in on; I don't really know any of the details.
 
  • #5
Take a tv (not lcd) and turn it on its side. what you see is the result of the magnetic field.
 
  • #6
Dirty D said:
Take a tv (not lcd) and turn it on its side. what you see is the result of the magnetic field.
What? Are you saying if I turn my TV on its side, I will see some funny pattern?
 
  • #7
That must be something with modern TV's, but I'm not going to bother trying it now. Back in the 70's, when I spent a good part of my time horizontally, I used to turn the TV on it's side so it would look right-side-up to me. The picture was still fine. What are you talking about?
 
  • #8
Dirty D said:
Take a tv (not lcd) and turn it on its side. what you see is the result of the magnetic field.
Um, no. Have you ever actually tried this (just to make sure, I just did)? The Earth's magnetic field is orders of magnitude too weak to affect a tv.
 
  • #9
Not necessarily.
Depends on how good the drive coil shadow mask registration for the pic tube in the color tv is.
Manufacturing has gotten better tolerances.
Generally it shows up as color tint changes in an object moving acrost the screen. Not image distortion.

In the 50's they had cancelation magnets in the cabinet that needed adjustment depending on the room location.
 

1. How is the Earth's magnetic field created?

The Earth's magnetic field is created by the movement of molten iron in the outer core of the planet. This movement generates electric currents, which in turn create the magnetic field.

2. What is the purpose of the Earth's magnetic field?

The Earth's magnetic field serves as a protective shield against harmful solar radiation and cosmic rays. It also helps animals and birds navigate and plays a role in the functioning of some electronic devices.

3. Is the Earth's magnetic field constant?

No, the Earth's magnetic field is not constant. It is constantly changing in strength and direction, and has even flipped its polarity numerous times throughout history.

4. How does the Earth's magnetic field affect our daily lives?

The Earth's magnetic field has a significant impact on our daily lives. It helps us determine direction and location, aids in communication and navigation systems, and protects us from harmful radiation.

5. Can the Earth's magnetic field change or disappear?

Yes, the Earth's magnetic field can change and even disappear. Geologic evidence shows that the Earth's magnetic field has reversed its polarity multiple times in the past, and it is possible for it to weaken or disappear completely in the future.

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