Pöörlemomenti

Pöörlemomenti, often translated as torque, is a measure of the rotational force acting on an object. It quantifies the tendency of a force to cause an object to rotate around an axis or pivot. The magnitude of the torque depends on three factors: the magnitude of the applied force, the distance from the pivot point to where the force is applied (known as the lever arm), and the angle between the force vector and the lever arm vector.

Mathematically, torque (often denoted by the Greek letter tau, τ) is calculated as the cross product of the position vector from the pivot to the point of force application and the force vector. In simpler terms, if the force is applied perpendicular to the lever arm, the torque is the product of the force's magnitude and the lever arm's length. If the force is applied at an angle, only the component of the force perpendicular to the lever arm contributes to the torque.

The SI unit for torque is the newton-meter (Nm). While numerically equivalent to the joule (the SI unit for energy), the newton-meter is preferred for torque to distinguish it from energy or work. Torque is a vector quantity, with its direction typically defined by the right-hand rule, indicating the axis of rotation.

In physics and engineering, understanding pöörlemomenti is crucial for analyzing the motion of rotating bodies. It plays a key role in the design of engines, motors, gears, and any system involving rotational motion, as it determines how effectively a force can initiate or change that rotation. For instance, a larger lever arm or a greater applied force will result in a larger pöörlemomenti, leading to a greater rotational effect.