Newton meter

Newton meter (Nm) is the SI unit of torque (also called "moment" in the physical sciences). It is a derived unit of measure that quantifies the force applied in a specific direction to move an object at a distance. One Newton meter is equal to the torque resulting from a force of one Newton applied perpendicularly to a moment arm which is one meter long.

Definition

The Newton meter is defined as the torque produced by a force of one Newton applied at the end of a lever arm that is one meter in length. The lever arm is measured from the axis of rotation to the point where the force is applied. Mathematically, torque (τ) can be expressed as:

\[ \tau = F \times r \]

where:

• \( \tau \) is the torque in Newton meters (Nm),
• \( F \) is the force applied in Newtons (N),
• \( r \) is the length of the lever arm in meters (m).

Applications

The Newton meter is widely used in various fields such as engineering, physics, and automotive to quantify the rotational force of engines, machinery, and other mechanical systems. It is crucial in the design and analysis of any system where forces and moments are of interest, ensuring that components are properly sized and can withstand the forces they will be subjected to during operation.

Measurement

Torque wrenches, which are commonly used in automotive and mechanical engineering, are calibrated in Newton meters to ensure the precise application of torque to fasteners like bolts and nuts. This precision is critical in applications where the tightness of screws and bolts is crucial for safety and operational efficiency.

Conversion

The Newton meter is part of the SI and is related to other units of measurement. It can be converted to other units of torque such as pound-force feet (lbf·ft) with the appropriate conversion factors. However, it is important to note that the Newton meter is the standard unit of torque in the SI system.

See also

• Torque
• Newton (unit)
• Meter
• International System of Units