3
votes
2answers
363 views

Why does magnet attract iron but not other metals?

While searching, i found this page: http://timesofindia.indiatimes.com/home/stoi/Why-does-a-magnet-attract-iron/articleshow/4298171.cms but it does not have full explanation. So Please tell full ...
0
votes
1answer
2k views

Dielectric Constant or Permittivity of Metals

I'm wondering what the dielectric constant or permittivity of metals is --particularly copper. Do metals have an infinite permittivity?
0
votes
1answer
103 views

What happens when molten metal cools within a strong magnetic field?

What happens when molten metal cools within a strong magnetic field? I don't know what more say, don't remember anything relevant to this in my uni text books.
1
vote
0answers
60 views

Maximise magnetic force at one point while minimizing at another

Is it possible to have a magnet that attracts one object strongly, but not another object behind that first object? Given an (electro-) magnet M above two thin parallel steel sheets P1 and P2 in the ...
1
vote
2answers
174 views

Why energy saving light bulbs contain rare earth?

Reading a french article talking about a recycling unit of rare earth from energy saving light bulbs near Lyon - France (here is the official press release of the Salvay company), I was wondering : ...
4
votes
4answers
6k views

In electrostatics, why the conductor is an equipotential surface?

Since the electric field inside a conductor is zero that means the potential is constant inside a conductor, which means the "inside" of a conductor is an equipotential region. Why books conclude ...
4
votes
3answers
13k views

In electrostatics, why the electric field inside a conductor is zero?

In electromagnetism books, such as Griffiths or the like, when they talk about the properties of conductors in case of electrostatics they say that the electric field inside a conductor is zero. I ...
1
vote
1answer
821 views

Properties to select suitable materials for making permanent magnets

I have read that soft iron is suitable for making a permanent magnet. Because it is required for permanent magnet to have high coercivity and high retentivity. Same text also said earlier that soft ...
1
vote
0answers
258 views

Electrical machines: electrical and mechanical properties of steels and cast iron

I would like to know a good source of information for the common metals (steels and cast iron). Information that I need are basically the mass density and the electrical conductivity or resistivity. ...