9478 / 2027

Chapter 17

Electromagnetic Forces

Name the field source, the selected body and the directions of current or velocity before finding a force.

Use field patterns, force laws and measurements to explain how conductors and charged particles respond to electric and magnetic fields.

Electric and magnetic beam motion, source patterns and field calculations, core effects, conductor forces and interactions, current-balance measurements and velocity selection. For 9478 (2027).

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  1. Motion in a uniform electric field

    Use charge sign and motion components to calculate force, acceleration and the complete exit state of an electron beam.

  2. Magnetic sources and field patterns

    Draw and interpret straight-wire, flat-coil and solenoid fields with a consistent viewpoint and current direction.

  3. Calculate a source magnetic field

    Choose the correct field expression and location for a wire, coil or solenoid, and explain the effect of a ferrous core.

  4. Force on a current-carrying conductor

    Use current, external field and angle to determine force, and define magnetic flux density through the perpendicular case.

  5. Measure magnetic flux density

    Separate the wire force from the magnet reaction and infer field strength from a balance change or force-current gradient.

  6. Forces between parallel currents

    Find each conductor's field at the other and use it to explain attraction, repulsion and equal interaction forces.

  7. Magnetic force on a charged particle

    Use charge sign, speed, angle and three-dimensional directions to find magnetic force and identify zero-force cases.

  8. Circular motion in a magnetic field

    Derive the magnetic orbit radius, track the velocity and inward force, and find the exit state at a field boundary.

  9. Select a beam speed

    Arrange opposing electric and magnetic forces and distinguish the selected speed from initial off-speed deflection.