Name: torque from a couple: solving forces
Uploaded: 2023-09-22T11:49:21.000Z
Duration: 1 min 30 s
Channel: JoVE

Consider a pipe attached to a coupling at point O on the x-axis in a three-dimensional coordinate system.
Two wrenches of length 0.12 meters apply an equal and opposite force of 120 newton along the z-axis. The wrenches are at a distance of 0.5 meters and 0.7 meters from point O along the x-axis.
Determine the couple moment of the system.
The couple moment about point O is determined as the sum of the cross-products of the position vectors and the applied forces.
rA and rB represent the position vectors originating from point O to points A and B, respectively.
The difference between the position vectors rA and rB is the vector r, which is the distance between the opposing forces.
The couple moment can be expressed in the determinant form as the cross-product of the position and force vectors.
The magnitude of the couple moment is determined by taking the square root of the sum of the squares of the components of the resulting vector.

moment of a couple: problem solving

The moment of couple is an essential concept in physics and engineering, used to calculate the rotational force, or torque, that is created when a couple &#8212;two equal and opposite forces&#8212;acts on an object.
The moment of a couple is found by multiplying the magnitude of one of the forces by the perpendicular distance between the line of action of the two forces. This creates a twisting force, which can be used to rotate an object. The moment of a couple is used to solve problems involving balanced and unbalanced forces.
The process of the moment of couple problem-solving involves several key steps. Initially, the relevant forces acting on the object must be identified and drawn in a clear and simple diagram. This can help to visualize the problem and make it easier to understand.
Next, find the vector associated with the perpendicular distance between the lines of action of the two forces. The cross product of the force vector and the perpendicular vector will give us the moment of the couple. The direction of the moment can be determined using the right-hand rule, which states that the direction of the torque is perpendicular to both the force and the distance vector.
Finally, the moment can be used to solve the problem at hand. This may involve calculating the overall torque on an object, determining the angular velocity or acceleration of a rotating object, or calculating the work done by the couple.

Moment of a Couple: Problem Solving

The moment of couple is an essential concept in physics and engineering, used to calculate the rotational force, or torque, that is created when a couple ...

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torque from a couple: solving forces

The moment of a couple is a key physics and engineering idea for finding torque, or rotational force. A couple is made of two equal and opposite forces that act on an object. When those forces work together, they create a twisting effect that can rotate the object.

The moment of a couple is calculated by multiplying the size of one force by the perpendicular distance between the two lines of action. That distance is the shortest straight-line distance between the force directions. This gives the moment needed to describe how strongly the couple turns the object.

Problem solving with a couple starts by identifying the forces on the object and drawing them in a clear, simple diagram. The next step is to find the vector for the perpendicular distance between the force lines. Then the cross product of the force vector and the perpendicular vector gives the moment of the couple.

The direction of the moment is found with the right-hand rule. This rule shows that the torque direction is perpendicular to both the force and the distance vector. Once the direction and size are known, the moment can help solve balanced and unbalanced force problems, find overall torque, determine angular velocity or angular acceleration, and calculate the work done by the couple.

Torque from a Couple: Solving Forces

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Couple Moment in Force Systems

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key terms and concepts

Learn how a couple creates torque, how to find its moment using force and distance, and how the right-hand rule helps solve rotation problems.

Torque from a Couple: Solving Forces | JoVE K12

JoVE Core Mechanical Engineering offers concise, easy-to-understand animated videos covering key topics such as equilibrium, forces, truss analysis, and structural mechanics. Explore their real-world applications, and witness these concepts in action through scientist-led experiments.

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Torque from a Couple: Solving Forces

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