Field Vectors; Rate Of Change Of Magnetic Flux Density - Pyramid T-1 User Manual

T1 Hall Probe System

13.2 Field vectors

The B field is a vector field, which you can decompose at any point into three orthogonal
components. Magnetic field lines by convention to point from the north pole to the south pole of
a magnet. A compass will point to the south pole of a magnet (thus there is a south magnetic
pole at the Earth's magnetic north pole).
N
S
N
S
The HP-1 probe measures the field component that is perpendicular to the flat face of the probe,
at the position of the red cross mark. If you orient the probe so that the field vectors point into
the bulls eye, you will get a positive field reading, as shown below. The figure also shows the
deflection direction of a positive ion beam for the illustrated field direction, and the conventional
current direction in the coils of an electromagnet producing the field.
i
N
S
N
S
i

13.3 Rate of Change of Magnetic Flux Density

Any conductor loop which encloses an area through which the magnetic flux is changing with
time will have a current induced in it. If the loop is not shorted, there will be a voltage induced
T1 User Guide
+ve field reading
+ve ions
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