Nichrome wire is a
nickel-
chromium resistance wire that is often used as a
heating element. The wire has a relatively high
resistance (measured
in
Ohms per
unit length) and heats up rapidly when current is run through it.
Nichrome has over 50 times the resistance of
copper with a resistance
of 100 micro-ohms/cm.
Nichrome wire is used in hot wire foam cutters.
In this application, it is important to realize that the wire will stretch some
when hot.
Nichrome wire is also used in biology.
One use is as part of a microbiological loop
for the sterile transfer of microorganisms.
Loops (which should contain more than 5cm of nichrome wire)
involve a completely closed loop of wire attached to a handle.
The loop can be sterilized (flaming the loop by
heating the loop and 3cm of wire to red-hot above a flame.
Let the loop cool for about 5 seconds before using it (and make sure
not to blow on it or wave it in the air, as this may contaminate it).
Another use in biology is in building electrophoresis boxes.