Final answer:
Torque in couples is the rotational effect produced by two equal and opposite forces acting on a body, where the torque is given by the product of one force and the distance between their lines of action.
Step-by-step explanation:
Torque in couples refers to a concept in physics, specifically within the branch known as mechanics. A couple is formed when two parallel forces of equal magnitude but opposite direction act on a body, creating a rotation without translation. The torque (τ) produced by a couple is calculated as the product of the magnitude of one of the forces (F) and the perpendicular distance (d) between the lines of action of these forces.
Mathematically, torque is expressed as τ = F × d. Here, the distance (d) is known as the arm of the couple. It's important to note that the torque produced by a couple is the same about any point in the plane, which is a unique characteristic of couples.