Torque
Definition
A rotational force that causes an object to rotate around an axis. Torque = Force × lever arm distance, measured in Newton-meters (N·m) or foot-pounds (ft·lb).
Why is Torque Important?
Torque is a core physics concept that describes the fundamental behavior of matter and energy. Understanding this principle enables engineers, students, and scientists to design better systems, solve real-world problems, and predict physical phenomena with precision.
Our physics calculators make it easy to compute values related to this concept, bridging the gap between theoretical understanding and practical application in engineering, education, and research.
What is Torque?
Torque (τ) is a rotational force that causes or tends to cause an object to rotate around an axis. It is the rotational equivalent of linear force and determines how effectively a force can cause angular acceleration.
Torque Formula
τ = F × r × sin(θ)
Where F = force, r = distance from axis (lever arm), θ = angle between force and lever arm. Maximum torque when θ = 90° (perpendicular).
Torque Units
| Unit | Equivalent | Context |
|---|---|---|
| Newton-meter (N·m) | SI standard | Engineering, specifications |
| Foot-pound (ft·lb) | 1.356 N·m | US automotive, construction |
| Inch-pound (in·lb) | 0.113 N·m | Small fasteners |
Torque in Automotive
| Vehicle/Engine | Torque | Meaning |
|---|---|---|
| Economy car (1.5L) | 110–150 ft·lb | Sufficient for daily driving |
| Midsize SUV (2.5L turbo) | 250–300 ft·lb | Good for towing, hills |
| Pickup truck (5.7L V8) | 400–500 ft·lb | Heavy towing capacity |
| Diesel truck | 600–1,000 ft·lb | Maximum towing, hauling |
| Tesla Model 3 (electric) | 310 ft·lb (instant) | Full torque from 0 RPM |
Common Bolt Torque Specs
| Application | Torque |
|---|---|
| Lug nuts (passenger car) | 80–100 ft·lb |
| Spark plugs | 12–18 ft·lb |
| Oil drain plug | 25–35 ft·lb |
| Head bolts | 60–85 ft·lb (varies by engine) |