can a magnet be de-magnetized if it is thrown down really hard?
478897
Yes if sufficient force is applied the force of impact will negate the magnetism. This is because the charged particles (electrons, neutrons, protons) will collide and confuse the flow of energy. Unless you have an elctromagnet then the magnetism will survive.\n\nSometimes if you drop a compass you will also make it useless as they are also magnetic
154800
From what I know about permanent magnets, the heat is the killer when you get near the transistion temperature of the material.  When you do this, the magnetic domains become randomly aligned again and the pole force gets reduced.  If you keep heating it, you can totally demagnatize the material.  In fact, during the manufacturing process, the material is heated very hot under a very strong magnetic field and cooled, allowing the aligned domains to be "frozen" making a high force pole.  \n\nSo in motor design, the aerodynamics of the rotor, the eddy currents generated while running, and the torque loads, will all contribute to heating the magnets.  If you can master the thermal design, you can make very powerful motors.
606554
Not that big!\n\nMagnetism is stronger than gravity by order of thousands.\nThe earths magnetic field is bigger and stronger than the earths gravitational field.\nMagnetism is stronger than gravity otherwise you would not be able to pick things up with a magnet
683402
It depends on the size of the magnet and its strength.  Putting an average strength magnet the size of a quarter next to a hard drive kills it.  However, in your laptop the hard drive has additional plastic shielding, but be warned, any magnet over the size of s nickel with one inch of your hard drive will fry it.  Remember that magnets go through plastic, cloth and other metals.
1142672
A few magnets will do the trick.... even a really large scientific one.
555635
Simple -\n\nJust de-energize the levitating gyro.  The photons will de-polarize and the accelerating magnetic field will collapse.\n\nBut you knew all that, right? You and your trick questions, s-rebel - you are such a tease!!  But a fun one!
304336
No there is no substance which can block magnetism except another magnet.  You can block electromagnetic energy quite easily depending on the strength.
92186
the magnet in the speaker will not only erase the recording on the tape it will leave magnetized spots on the tape where the speaker touched. The tape will then need to be demagnetized before being used again .
110961
you could sew flexible magnets into fabric. You may even be able to mount magnets into fabric like you would a button.  \n\nOK I GOTTA ASK... What are you making?
226823
you can't block or absorb, but can always divert it. get a cage of good ferro-magnetic material, and magnetic field will not pass inside the cage. \n\nIt is similar to electric charge.
526990
It can be demagnetized by being placed into an electromagnetic field.  Old ringer phones would produce such a field when the bell rang but I don't think a cell phone will produce an electromagnetic field sufficient to demagnetize a motel room key.\n\nAn interesting side note:  If you have an eel skin billfold, it will, over time, demagnetize your credit cards, motel keys, etc.  I don't know why but it will.
145532
think of your harddrive like an old fashioned record.  It is basically a blank sheet until something is written to it.  A PC writes data to the disks of a hard drive by applying a magentic field to the surface of the disk and that forces the disk to orientate the surface into a certain pattern.  When the hard drive comes back around and attempts to get that data again it can detect in which order that data was written (1 or 0) and then the hard drive sends data to the rest of the pc to do whatever you want it to.\n\nDemagnetizing a drive is a way to use an extremely powerful magnet to force any data that has been written to the harddrive to "mess itself up" so that it is no longer readable.\n\nNot really practical for Joe User, but I do know that government, law offices and some medical groups will send old hard drives to companies to have them destroyed in this manner.
516869
magnet-damaged\n\nwhat do u mean by it?
866029
Strong and patented super magnets usually do not or never wear out and do not lose their magnetic charge so permanent use for a long period is guaranteed. Hard chromium coated magnets are known to be good.\n\nThere are also kinds of magnets  like an ordinary ceramic magnets which lose their magnetic charge with time or when exposed to heat. Just be careful in choosing the kind of magnet  itself.♥
1137048
Well it is certainly not a "perpetual motion" type of device. Magnets gradually lose their magnetism as their "disorder" increases. Their "disorder" increases when they contribute to "order" in ferrous objects in their proximity. Need to increase the "order" in your magnet? Wrap a coil around it and connect it to a DC source. Different materials will "retain" different amounts of residual magnetism ("order") after the power source is switched off. Natural magnets would have been exposed over centuries to small, but significant electrical stresses during their formation. They too would gradually lose it as their "disorder" increases. To answer your question - magnets owe it to electrical energy imprinted in ferrous memory.
648293
This is a magnetic flywheel.  The spinning magnets will induce a voltage across the coil of wire.  If you draw current from the wire, that current will induce a magnetic field which will exert a torque on the magnets, slowing them down.  The total electrical energy you can get out of the system will never exceed the initial kinetic energy of the rotating magnets.\n\nThe thing slowing down the magnets is not friction, it's an electromagnetic force, and even if you eliminate friction completely, the magnetic torque will spin down your magnets quite handily as soon as you start extracting energy from the system.
703613
If they are too strong to pull apart directly, try sliding them.\n\nIf this doesn't work, find an even stronger magnet and put something between it and the other two first.