Gauge Versus Winds for Magnet
When using a copper coil and magnets to generate an EMF
is it the number of "wraps" in the coil or the amount of copper in
the coil that is more important? Is a smaller gauge wire with more
wraps better than a larger gauge wire with fewer wraps?
The number of turns (wraps) is directly proportional to the EMF that
you can obtain for a given area within a magnetic field. Generator
design becomes an engineering problem in which you try to balance size
and performance. For further reference, check out Faraday's law. It
states that the magnitude of EMF is equal to the number of turns times
the time rate of change of the magnetic flux.
Hope this helps.
There are three major factor to consider: number of loops, density of
loops, radius of the loops. If the number of loops is large enough and
the radius is small enough, then you have a solenoid. Density of loops
becomes the major concern. If the coil is much wider than it is long,
number of loops and average radius are the major concerns: N/r. As
most electromagnets are in the form of a coil that is at least as long
as it is wide, a solenoid is probably a good model.
The advantage of thin wire is that you get more loops per centimeter.
The advantage of thick wire is that you can handle more current. The
product of the two (current times loops per centimeter) is what
determines the magnetic field inside the coil and near the openings. If
you can limit the current, then the narrower gauge gives the same
magnetic field with less current. This is safer. If the current cannot
be limited, then use the wider gauge to prevent overheating of the coil.
In either case, a longer wire wrapped in a coil of more loops per
centimeter (i.e. more layers, smaller radius) should provide the
Dr. Ken Mellendorf
Illinois Central College
Question as I understand it is the windings say the number have impact on its
use or result.
A core/ transformer frequently called or say electromagnetis and similar. The
larger the magnet is both dependent on the number of windings and the thickness..
Please start with a look at ohms law and follow by inductance and magnetism there.
Remember the greater the windings we are increasing the amount of current handled
and thickness i.e. tolerances the amount of voltage that is dealt with,......
all deal with the amount of power as an end result. Keep in mind also that
materials can change parameters, I also for the more advanced to read about
super conducting etc.
Prof. Przekop, Physicist
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Update: June 2012