Tesla (unit)

The tesla (symbol T) is the SI derived unit of magnetic flux density (or magnetic induction). It is a unit to define the intensity (density) of a magnetic field.

Definition

1 T = 1 Wb·m^{-2^{= 1 kg·s^–2·A^–1= 1N·A^–1·m^{-1^{= 1 kg·s^–1·C^–1}}}}

SI multiples

Origin

The tesla was adopted in 1960, and named in honor of the Serbian-American inventor and electrical engineer Nikola Tesla.

Explanation

The tesla is the value of the total magnetic flux (a magnet's "power") divided by area. Hence, reducing the affected area will generally increase the magnetic flux density.

This will continue to occur until the material becomes magnetically saturated and/or the magnetic field "leakage" increases so fast that no additional tesla gains are possible.

Conversions

1 tesla is equivalent to:

10,000 gauss (G), used in CGS system
10⁹ gammas (γ), used in geophysics

Examples

In outer space the magnetic flux density is between 0.1 and 10 nanoteslas (10⁻¹⁰ T and 10⁻⁸ T),
in the Earth's magnetic field at latitude of 50° is 58 µT (5.8×10⁻⁵ T) and on the equator at a latitude of 0° is 31 µT (3.1×10⁻⁵ T),
in the magnetic field of a huge horseshoe magnet 1 millitesla (0.001 T),
a large 30 pound loudspeaker magnet will have a coil gap of 1 T
in medical magnetic resonance imaging up to 7 T, experimentally up to 20 T,
in a sunspot 10 T,
strongest continuous magnetic field yet produced in a laboratory (Florida State University's National High Magnetic Field Laboratory in Tallahassee, USA), 45 T [http://www.magnet.fsu.edu/news/pressreleases/121799.html,
strongest (pulsed) magnetic field yet obtained non-destructively in a laboratory (Koichi Kindo at Osaka University ^*), 80 T,
strongest (pulsed) magnetic field ever obtained (with explosives) in a laboratory (Sarov, Russia), 2800 T,
on a neutron star 1 to 100 megateslas (10⁶ T to 10⁸ T),
on a magnetar, 0.1 to 100 gigateslas (10⁸ to 10¹¹ T),
maximum theoretical field strength for a neutron star, and therefore the upper bound thus far for any known phenomenon, 10¹³ T (10 terateslas).

Reference

sizes.com - date of adoption

SI derived units | Units of magnetic flux density | Nikola Tesla