Definition

1. Noun (Physics/Mechanics):
   • Couple: A system of two forces that are parallel, equal in magnitude, but opposite in direction, acting at two different points on a rigid body. The primary effect of a couple is to produce or change the rotation of the body without causing any translational motion.

Usage Examples

• Noun:
  • Ngẫu lực tác dụng lên vô lăng làm nó quay. (A couple acts on the steering wheel, causing it to rotate.)
  • Hiệu ứng của ngẫu lực là mômen thuần túy. (The effect of a couple is a pure moment.)
  • Để mở van, bạn cần tạo ra một ngẫu lực. (To open the valve, you need to apply a couple.)

Advanced Usage

• "Ngẫu lực quay": A rotating or torque couple, often emphasized in dynamic systems.
  • Động cơ tạo ra ngẫu lực quay để làm quay trục. (The engine generates a rotating couple to turn the shaft.)

Variants and Related Words

• Mômen lực / Mômen (n): Moment of a force / Torque. While a couple is a specific pair of forces, torque is the rotational effect produced by any force or couple.

  • Mômen lực phụ thuộc vào khoảng cách từ điểm tựa. (The moment of a force depends on the distance from the pivot point.)

• Cặp lực (n): Pair of forces. This is a more general, descriptive term for any two forces, not necessarily forming a pure couple.

  • Hệ thống chịu tác dụng của một cặp lực phức tạp. (The system is subjected to a complex pair of forces.)

Synonyms

• Couple (in physics/engineering)
• Force couple
• Pure moment (refers to the rotational effect)

Key Concept Explanation

A couple is a fundamental concept in mechanics. Unlike a single force, which can cause both linear acceleration and rotation, a couple produces only rotation. A common example is the forces applied by your two hands when turning a steering wheel: you push one hand forward and pull the other back with equal force, creating a couple that rotates the wheel without pushing it sideways.

1. (vật lý) Couple