Name: torque on a flywheel: direction and size
Uploaded: 2023-09-22T11:49:20.000Z
Duration: 1 min 18 s
Channel: JoVE

Torque, or the moment of a force, is the ability of a force to rotate a body about a point or an axis that is not in the line of action of the force. It is a vector quantity.
Consider an example of a flywheel, where a force is applied to rotate the flywheel about point O.
Here, the moment arm is the perpendicular distance from point O to the line of action of the force.
The magnitude of the force is multiplied by the moment arm to obtain the magnitude of the moment. So, the unit for the moment of a force is newton-meter.
Its magnitude is maximum when the applied force is tangential to the flywheel.
The right-hand rule is used to determine the direction of the moment. If the curled fingers represent the rotation caused by the moment, then the thumb represents the direction of the moment.
Conventionally, the positive moment denotes the counterclockwise rotation, while the negative sign denotes the clockwise rotation of the flywheel.

moment of a force: scalar formulation

The moment of a force, also known as torque, measures the ability of the force to create rotational motion in a body about an axis. It is a vector quantity, meaning it has both magnitude and direction. This concept is used extensively in engineering, physics, and mechanics.
Consider a simple example of a flywheel being rotated about a point, O, by applying a force to it. In this case, the moment arm is the perpendicular distance between the point O and the line of action of the force. The magnitude of the moment is calculated by multiplying the magnitude of the force by the moment arm. This quantity has the unit of newton-meter (N-m).
The maximum moment occurs when the force applied is tangential to the flywheel, as it is perpendicular to the radius of the flywheel. The magnitude of the moment also increases with the magnitude of the applied force and the length of the moment arm.
The right-hand rule determines the direction of the moment. If the fingers of the right-hand curl in the direction of the rotational motion produced by the moment, then the thumb points in the direction of the moment. Conventionally, a positive moment denotes counterclockwise rotational motion, while a negative sign denotes clockwise rotational motion.
The moment of a force is essential for understanding the dynamics of machines and structures. It is a critical tool for analyzing and predicting the behavior of complex mechanical systems.

Moment of a Force: Scalar Formulation

The moment of a force, also known as torque, measures the ability of the force to create rotational motion in a body about an axis. It is a vector ...

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torque on a flywheel: direction and size

Torque, or the moment of a force, describes how a force can make an object turn about an axis. It is a vector quantity, so it has both size and direction. This idea is important in physics, mechanics, and engineering.

A simple flywheel example shows how torque works. The flywheel rotates about point O when a force is applied to it. The moment arm is the perpendicular distance from point O to the line of action of the force. The moment, in newton-meter (N-m), is found by multiplying the force by the moment arm.

The largest moment happens when the force acts tangentially to the flywheel. In that case, the force is perpendicular to the radius of the flywheel. The moment also gets larger when the applied force is larger or when the moment arm is longer.

The right-hand rule gives the direction of the moment. If the fingers of the right hand curl in the direction of the rotation, the thumb points along the moment direction. By convention, counterclockwise motion is positive, and clockwise motion is negative. This helps in analyzing machines and structures and in predicting how mechanical systems behave.

Torque on a Flywheel: Direction and Size

Torque, or the moment of a force, describes how a force can make an object turn about an axis. It is a vector quantity, so it has both size and direction. This idea is important in physics, mechanics, and engineering. A simple flywheel example shows how torque works. The flywheel rotates about point O when a force is applied to it. The moment arm is the perpendicular distance from point O to the line of action of the force. The moment, in newton-meter (N-m), is found by multiplying the force...

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key terms and concepts

Learn how torque, or moment of a force, depends on force size, moment arm length, and direction using a flywheel example and the right-hand rule.

Torque on a Flywheel: Direction and Size | 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 on a Flywheel: Direction and Size

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