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Hall effect and sensors
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Hall probes measure magnetic field.
Hall probes use the transverse voltage to measure B; they are used in position sensors, wheel-speed sensors and phones.
Output voltage ∝ B.
Temperature drift needs compensation.
In more detail
The Hall effect is the voltage that appears across a conductor carrying current in a magnetic field. Hall sensors use this effect to measure magnetic fields and detect positions.
Real-world uses
- Hall sensors detect rotor positions in brushless motors.
- Car wheel speed sensors use Hall effect devices.
- Car manufacturers use Hall sensors to detect the position of a shaft or the speed of a wheel.
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Frequently asked questions
What causes the Hall voltage?
Magnetic force pushes charges sideways until the resulting electric field balances it.
Can Hall sensors measure sign of charge?
Yes, the polarity of the voltage reveals the carrier type.
How does a Hall probe measure the field?
It measures the voltage produced across a conductor when a current passes through it in the magnetic field.
Related topics in Magnetism & Induction
Van Allen belts · Superconducting magnets · Magnetic field of moving charge · Magnetic energy density · Magnetic pressure · Lorentz force law