What is torque defined as?

Torque is defined as the rotational equivalent of linear force. It is the measure of the force that can cause an object to rotate about an axis. The correct formulation for torque is the product of the force applied and the distance from the pivot point to the point where the force is applied, known as the force arm. This relationship can be expressed with the formula: torque = force x distance (or force arm).

In a practical sense, when a force is applied at a distance from the pivot point—like when using a wrench—the amount of torque generated depends not only on the magnitude of the force but also on how far from the pivot that force is applied. For example, using a longer wrench allows you to apply the same force but generates more torque, making it easier to turn a bolt.

The other choices do not accurately describe torque. Mass times acceleration is related to linear motion (Newton's second law), weight times distance pertains to concepts involving gravitational force and lever arms in a non-rotational context, and speed multiplied by time refers to distance traveled, which is also unrelated to the concept of torque. Thus, the formulation of torque as force multiplied by the force arm clearly defines its role in rotational dynamics.