Magnetic Field Energy


by iedoc
Tags: energy, field, magnetic
iedoc
iedoc is offline
#1
Apr3-12, 08:04 AM
P: 8
The idea is really simple, but it might not come out in words the same.

Is the energy produced from a magnet pushing another magnet away GREATER than the energy needed for a magnet to enter a magnetic field from the side?

I'll try to be more specific. You have two magnets, one in your left hand and one in your right hand, who's north poles (or south) are facing each other, so they will be pushed away when they get too close. If you put keep their orientation (left magnets north is facing right, and right magnets north is facing left) and put the left magnet above the right magnet, then "slide" or push the right magnet up into the left magnets magnetic field so that it gets pushed to the right, will the energy of the magnet being pushed to the right as it enters the left magnets magnetic field be GREATER than the energy it took to push the right magnet into the left magnets magnetic field?
Phys.Org News Partner Physics news on Phys.org
Sensitive detection method may help impede illicit nuclear trafficking
CERN: World-record current in a superconductor
Beam on target: CEBAF accelerator achieves 12 GeV commissioning milestone
berkeman
berkeman is online now
#2
Apr3-12, 12:36 PM
Mentor
berkeman's Avatar
P: 39,578
Quote Quote by iedoc View Post
The idea is really simple, but it might not come out in words the same.

Is the energy produced from a magnet pushing another magnet away GREATER than the energy needed for a magnet to enter a magnetic field from the side?

I'll try to be more specific. You have two magnets, one in your left hand and one in your right hand, who's north poles (or south) are facing each other, so they will be pushed away when they get too close. If you put keep their orientation (left magnets north is facing right, and right magnets north is facing left) and put the left magnet above the right magnet, then "slide" or push the right magnet up into the left magnets magnetic field so that it gets pushed to the right, will the energy of the magnet being pushed to the right as it enters the left magnets magnetic field be GREATER than the energy it took to push the right magnet into the left magnets magnetic field?
No. There is no free energy.
iedoc
iedoc is offline
#3
Apr3-12, 01:05 PM
P: 8
i know energy cannot be created or destroyed. I think I might have asked the question wrong. basically what i'm wondering is if we are able to use the energy from the magnetic field. for example, if we are able to have a magnet pushed away from another magnet, into another magnets magnetic field, then have that magnet push the magnet away into another magnet's magnetic field, and continue doing that, so that the energy from the magnetic fields keeps the magnet in motion. does that make sense? I have it all perfectly laid out in my head, i just can't find a very clear description of what i'm thinking.

it's really a such a simple idea i doubt it would work, because i'm sure if it did, it would have been discovered a long time ago. but i'm still curious since i've never heard of it before

berkeman
berkeman is online now
#4
Apr3-12, 01:07 PM
Mentor
berkeman's Avatar
P: 39,578

Magnetic Field Energy


Quote Quote by iedoc View Post
i know energy cannot be created or destroyed. I think I might have asked the question wrong. basically what i'm wondering is if we are able to use the energy from the magnetic field. for example, if we are able to have a magnet pushed away from another magnet, into another magnets magnetic field, then have that magnet push the magnet away into another magnet's magnetic field, and continue doing that, so that the energy from the magnetic fields keeps the magnet in motion. does that make sense? I have it all perfectly laid out in my head, i just can't find a very clear description of what i'm thinking.
No, the motion would slow down and stop. Perpetual Motion Machines (PMMs) of all sorts have been explored and debunked as impossible.

We do not discuss PMMs or Free Energy schemes at the PF. Here are two good links for understanding why PMMs and Free Energy cannot work:

http://wiki.4hv.org/index.php/Free_Energy_Debunking

http://en.wikipedia.org/wiki/Perpetual_motion


Register to reply

Related Discussions
Electric field from magnetic field and kinetic energy Introductory Physics Homework 0
Energy of magnetic field created by magnetic dipoles in a shphere. Classical Physics 1
deriving the energy of a magnetic dipole in a magnetic field Introductory Physics Homework 8
deriving the energy of a magnetic dipole in a magnetic field Classical Physics 1
Energy in Magnetic Field Quantum Physics 5