couple

In physics jargon the couple is a pair of anti-parallel forces, of equal magnitude, seperated by a distance.

The torque of a couple is equal to the magnitude of the force(s) multiplied by the seperation distance.

Torque = Fa (Where F is the magnitude of each force, and a is the seperation distance)

A couple is an explicit definition which comes in handy when dealing with torque in static equilibrium! (Eg. An 'L'-Shaped Formula 1 style car jack can be modelled as a couple)

Cou"ple (k?p"'l), n. [F. couple, fr. L. copula a bond, band; co- + apere, aptum, ti join. See Art, a., and cf.Copula.]

1.

That which joins or links two things together; a bond or tie; a coupler.

It is in some sort with friends as it is with dogs in couples; they should be of the same size and humor. L'Estrange.

I'll go in couples with her. Shak.

2.

Two of the same kind connected or considered together; a pair; a brace. "A couple of shepherds." Sir P. Sidney. "A couple of drops" Adduson. "A couple of miles." Dickens. "A couple of weeks." Carlyle.

Adding one to one we have the complex idea of a couple. Locke.

[Ziba] met him with a couple of asses saddled. 2 Sam. xvi. 1.

3.

A male and female associated together; esp., a man and woman who are married or betrothed.

Such were our couple, man and wife. Lloyd.

Fair couple linked in happy, nuptial league. Milton.

4. Arch.

See Couple-close.

5. Elec.

One of the pairs of plates of two metals which compose a voltaic battery; -- called a voltaic couple or galvanic couple.

6. Mech.

Two rotations, movements, etc., which are equal in amount but opposite in direction, and acting along parallel lines or around parallel axes.

⇒ The effect of a couple of forces is to produce a rotation. A couple of rotations is equivalent to a motion of translation.

© Webster 1913.

Cou"ple, v. t. [imp. & p. p. Coupled (k?p"'ld); p. pr. & vb. n. Coupling (-l?ng).] [F. coupler, fr. L. copulare. See Couple, n., and cf. Copulate, Cobble, v. ]

1.

To link or tie, as one thing to another; to connect or fasten together; to join.

Huntsman, I charge thee, tender well my hounds, . . . And couple Clowder with the deep-mouthed brach. Shak.

2.

To join in wedlock; to marry.

A parson who couples all our beggars. Swift.

© Webster 1913.

Cou"ple, v. i.

To come together as male and female; to copulate.

Milton. Bacon.

© Webster 1913.