Right-hand rule

Definition

The right-hand rule is a mnemonic for understanding the orientation of axes in 3-dimensional space. It is commonly used to determine the direction of angular velocity, torque, and magnetic fields.

5 Must Know Facts For Your Next Test

1. To use the right-hand rule for rotation, point your thumb in the direction of the axis of rotation. The curl of your fingers shows the rotational direction.
2. For torque, point your fingers in the direction of force application and curl them towards the pivot point; your thumb points in the torque's direction.
3. When dealing with cross products (e.g., angular momentum), align your index finger with the first vector and middle finger with the second vector; your thumb then points in the resultant vector's direction.
4. It helps visualize positive (counter-clockwise) and negative (clockwise) rotations around an axis.
5. Right-hand rule is essential for interpreting vector quantities that follow a rotational or circular motion.

Review Questions

• How do you use the right-hand rule to determine the direction of angular velocity?
• What does your thumb represent when using the right-hand rule for torque?
• Describe how to apply the right-hand rule to find a cross product.

Related terms

Torque:

A measure of how much a force acting on an object causes that object to rotate. Calculated as $\tau = r \times F$.

Angular Velocity:

The rate at which an object rotates or revolves relative to another point, often measured in radians per second.

Cross Product:

A binary operation on two vectors in three-dimensional space, producing a third vector perpendicular to both original vectors.