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Updated Mar 17, 2026

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5 pages

Cool Science: Fleming's Rule, Hall Voltage, and Forces in Wires!

Xin Ying Pua

@notesxyz

A comprehensive guide to magnetic fields and particle accelerators, covering... Show more

1 / 5

# MAGNETIC FIELDS

magnetic fields

- b-fields

- force that exerts a force on magnetised materials, moving charges & electrical currents

-

Hall Voltage

This section explains the Hall effect and its relationship to magnetic fields in current-carrying conductors.

Definition: Hall voltage is the potential difference induced across a conductor when a magnetic field is applied perpendicular to the current flow.

Highlight: The Hall voltage (VH) is proportional to the magnetic field strength (B) for a fixed current.

Example: When electrons in a conductor experience both electric and magnetic forces, they reach equilibrium when these forces become equal $Bqv = VH/d$ .

Current Carrying Wires and Solenoids

This page details the interactions between current-carrying wires and the properties of solenoids.

Definition: A solenoid is a coil of current-carrying wire that produces a nearly uniform magnetic field inside its core.

Highlight: Parallel current-carrying wires attract when currents flow in the same direction and repel when currents flow in opposite directions.

Example: The force between parallel current-carrying wires is given by F = (μ₀I₁I₂l)/(2πa), where μ₀ is the permeability of free space.

Uniform Electric Fields

This section explores the behavior of charged particles in uniform electric fields.

Definition: A uniform electric field is a region where the electric force is constant in both magnitude and direction.

Highlight: Charged particles follow parabolic trajectories when entering a uniform electric field at 90°.

Example: The acceleration of a charged particle in a uniform electric field is given by a = (Vq)/(md), where V is voltage, q is charge, m is mass, and d is distance between plates.

Particle Accelerators

This final section covers different types of particle accelerators and their operating principles.

Definition: Particle accelerators are devices that use electromagnetic fields to propel charged particles to high speeds.

Highlight: Three main types of accelerators are discussed: linear accelerators (linacs), cyclotrons, and synchrotrons.

Example: In a cyclotron, the frequency of particle rotation is independent of velocity and path radius, given by f = (Bq)/(2πm).

Vocabulary: Linac - Linear accelerator that uses alternating electric fields to accelerate particles in a straight line.

Magnetic Fields and Forces

Definition: Magnetic fields $B-fields$ are forces that exert influence on magnetized materials, moving charges, and electrical currents.

Highlight: The force on a current-carrying wire in a magnetic field is given by F = BIlsinθ, where B is magnetic flux density, I is current, l is length, and θ is the angle between B-field and current.

Example: A moving charge in a magnetic field experiences a force F = Bqv, causing it to move in a circular path due to constant centripetal force.

Vocabulary: Tesla (T) - the unit of magnetic flux density, representing the field strength that causes a wire carrying 1A to experience a force of 1N per meter.

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Physics

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617

•

Updated Mar 17, 2026

•

5 pages

Cool Science: Fleming's Rule, Hall Voltage, and Forces in Wires!

Xin Ying Pua

@notesxyz

A comprehensive guide to magnetic fields and particle accelerators, covering fundamental principles of electromagnetic interactions and their practical applications in modern physics.

Fleming's left hand rule for magnetic fields helps determine the direction of force on current-carrying conductors
The Hall... Show more