Couple and its Torque

A couple is a system of forces that has a consequent (net or total) moment but no resultant force in mechanics.

Force couple is a better term. It has the effect of causing rotation without translation. Force couples are free vectors in rigid body mechanics, which means their effects on a body are independent of the point of application.

A torque is the resulting moment of a couple. This is not to be confused with the term torque, which is essentially a synonym for moment in physics. Torque, on the other hand, is a type of moment. Torque has unique qualities that moment does not, including the ability to be independent of a reference point.

Torque of a Couple:

Consider A and B as two places on a body where two equal-force F forces are applied in opposite directions parallel to one another. As a result of the force, this body begins to rotate counter-clockwise or tries to rotate about the axis passing through 0. Keep in mind that if these two equal forces have the same path of action or act at the same spot, they will cancel each other out.

As a result of a couple’s activity, a torque is applied to the body, causing it to spin around a fixed point.

τ =F× r

The torque exerted to the body is shown by this symbol. The quantity of force multiplied by the perpendicular distance between the two forces equals the magnitude of torque.

Characteristics of couple :

• The couple does not induce translational motion because the two forces that make up the couple are equal and opposing.

• When it is applied to a body, the net resultant force is zero.

• It creates pure rotational motion in the body because the algebraic sum of the moments of the two forces around any point in their plane is not zero.

• The size and direction of a couple’s moment about any point on its plane are both constant.

Difference between torque and couple:

Students studying physics are frequently exposed to notions like moment, torque, and coupling, and these terminology are frequently misunderstood. Although there are some parallels between a torque and a couple, there are also some significant differences that will be discussed in this essay.

Torque is a specific type of force capable of rotating an object around an axis. While a force is defined as a push or a pull, torques are better described as a twist. Torque can be felt while turning the steering wheel of a car with your hands or when trying to unscrew a nut with a tool. A torque is a force that causes something to turn.

When the applied force vectors sum up to zero, the force is referred to as a couple, and the moment is referred to as a torque. A pure moment is often referred to as a couple. When two equal but opposing forces act on a body whose lines of force do not overlap, the most fundamental type of couple occurs. A couple’s SI unit is the Newton-meter.

Torque Limiter coupling:

A single moment or action might cause critical driving components to fail or fracture. When a spinning component experiences torques that exceed what the system is designed to tolerate, this is referred to as mechanical overload. Any rotational process may generate a lot of torque, and if something goes wrong, all of that power might damage impacted components such as couplings, drive or motor shafts, and/or gears.

Simply, these devices safeguard rotating components from mechanical stress. This category includes clutches, brakes, and torque limiters. Torque Limiters, in particular, function by sliding under torque overload to keep driven components from being subjected to high torque loads.

In the situation of a torque overload, the Torque Limiter can preserve essential equipment by separating the driving shaft from the driven components.

Torque Limiters keep torque-based forces from exceeding the set point. These pieces avoid mechanical overload and failures by restricting torque forces to what the rotatable components can safely handle. They can function alone or in conjunction with electrical sensors. Overload clutches are another name for mechanical torque limiters.

Torque Limiters can be used to protect any machine that has spinning parts. A Torque Limiter can guarantee that torque never reaches critical levels if there is any chance of a drive shaft transferring too much torque to the driven shaft or tangential portions. The components link the two spinning bodies and provide a mechanism of disconnect.

Applications of couple:

• We use our hands to add force to the handle of a moving bicycle when turning it.
• When we open and close the tap’s spout.
• A pair of forces are delivered with the fingers while opening and shutting the device’s lid.
• When the pencil is held between the palms of both hands and rotated in the opposite way, the pencil begins to rotate.
• The churn starts rotating while holding the ends of the rope with one hand and running the other hand in the opposite direction; this is also an example of a pair.

Conclusion:

A couple is made up of two equal, opposite, parallel forces that are not acting in the same direction. In any direction, the vector sum of the components of the two forces is obviously zero. However, the sum of the moments of the two forces around a point is not zero. A couple is a system of forces that has a consequent moment but no resultant force in mechanics. A torque is the resulting moment of a couple. As a result of a couple’s activity, a torque is applied to the body, causing it to spin around a fixed point. The couple does not induce translational motion because the two forces that make up the couple are equal and opposing.