|MadSci Network: Physics|
1 milligauss = 10^(-3) Gauss = 0.001 Gauss 1 Gauss = 10^(-4) Tesla = 0.0001 Tesla 1 Tesla = 1 Weber/m^2 = 1 kg/s^2/A The strength of electromagnetic field is affected by the sources (currents and charges) and the environment. In most cases it is proportional to the strength of the sources. For example, if your magnetic field is generated by a current, then if you double the strength of the current, the strength of your magnetic field will also double. If you have a long straight wire on which there is a current of 0.01A (you can use a 1.5V battery and a 150ohm resistor to generate such a current), then at a distance of 0.1m from the wire the strength of the magnetic field is mu0 * I / (2 * pi * r) N/A^2*A/m = 4 * pi * 10^(-7) * 0.01 / ( 2 * pi * 0.1) kg*m/s^2/A/m = 2 * 10^(-8) kg/s^2/A = 2 * 10^(-8) Tesla = 2 * 10^(-4) Gauss = 0.2 milligauss Therefore, milligauss is quite small a unit for magnetic field strength. You can easily generate magnetic field of several milligauss. The following page contains information about the units for magnetic field strength. http://physics.nist.gov/cuu/ Units/units.html The following page did some measurement of the magnetic field near high-voltage transmission line. The results are in milligauss (mG). http://www.vitatech.net/map4.html
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