Question 1

What is the difference between B field and H field?

Accepted Answer

B (Tesla) is total magnetic flux density including material magnetization. H (A/m) is external field strength excluding material response. In vacuum, B = mu0 * H where mu0 = 4pi x 10^-7.

Question 2

What is Tesla?

Accepted Answer

Tesla is the SI unit of magnetic flux density, named after Nikola Tesla. Earth's field is 25-65 microTesla. MRI scanners use 1.5-3 T. Neodymium magnets reach about 1.4 T at the surface.

Question 3

What is Gauss?

Accepted Answer

Gauss (G) is the CGS unit: 1 G = 10^-4 T = 0.1 mT. Earth's field is about 0.5 G. Fridge magnets are about 50 G. Neodymium magnets reach 14,000 G.

Question 4

What is Oersted?

Accepted Answer

Oersted (Oe) is the CGS unit of magnetic field strength H: 1 Oe = 79.577 A/m. Named after Hans Christian Orsted who discovered electromagnetic induction.

Question 5

What magnetic fields do everyday objects produce?

Accepted Answer

Fridge magnet: ~5 mT (50 G). Neodymium magnet: ~0.5-1.5 T. MRI scanner: 1.5-7 T. Earth's field: 25-65 muT. Power line at 1m: ~1-10 muT.

T	1
mT	1000
μT	1.00000e+6
nT	1.0000e+9
G	10000
mG	1.0000e+7

A/m	1
kA/m	0.001
Oe	0.0125664

Earth's magnetic field	25–65 μT
Fridge magnet	~5 mT
Neodymium magnet (surface)	~1–1.4 T
MRI scanner (clinical)	1.5–3 T
Research MRI	7–10.5 T
Junkyard electromagnet	~1 T

Conversor de Campo Magnético

Magnetic Flux Density (B field)

Magnetic Field Strength (H field)

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