toroid

Thân thiện

A child holds a colorful plastic toroid among building blocks.

Definition

1. Noun:
   • A ring-shaped surface generated by rotating a circle around an axis that does not intersect the circle: This is the geometric definition. It describes the hollow, three-dimensional shape created by sweeping a circle through space.
   • The doughnut-shaped object enclosed by a torus: This refers to the solid, three-dimensional object that has the shape of a doughnut or a lifebuoy.

Usage Examples

• Noun:
  • In geometry, a toroid is a surface of revolution with a hole in the middle.
  • The magnetic field was confined within the toroid of the experimental reactor.
  • A bagel is a good everyday example of a solid toroid.

Advanced Usage

• In Electromagnetism: A toroid often refers specifically to a coil of wire wound in a tight, continuous helix around a ring-shaped (toroidal) core. This configuration is used to create inductors with very low external magnetic fields.
  • The engineer designed a toroid for the power supply to minimize electromagnetic interference.
• In Plasma Physics: A toroid describes the shape of the containment vessel in devices like tokamaks, which are used in nuclear fusion research.
  • The superheated plasma is held within the magnetic fields of the large toroid.

Variants and Related Words

• Toroidal (adj): Having the shape or properties of a toroid.
  • The device uses a toroidal magnetic field.
• Torus (n): In mathematics, this term is often used interchangeably with "toroid" for the surface. In common usage, "torus" can also refer to the solid shape.
• Annulus (n): A two-dimensional ring shape (like a flat washer). A toroid can be thought of as a rotated annulus.

Synonyms

• Ring
• Doughnut shape
• Anchor ring

Related Terms and Concepts

• Surface of revolution: A surface created by rotating a curve around an axis. A toroid is a specific type of surface of revolution.
• Solids of revolution: The 3D solid created by rotating a 2D shape around an axis. The solid toroid is an example.
• Poloidal and Toroidal Directions: In a toroidal shape, the toroidal direction goes the long way around the main hole (like following the circle of the doughnut), while the poloidal direction goes around the smaller cross-section (like going through the hole of the doughnut).

Học thuật

Noun

1. a ring-shaped surface generated by rotating a circle around an axis that does not intersect the circle
2. the doughnut-shaped object enclosed by a torus

Từ đồng nghĩa

• torus