For 10 points, name this measure of how much a force acting on an object causes it to rotate.
In mechanics, Varignon's theorem deals with this quantity. When a system of forces has a nonzero value for this quantity but no resulting force, it is called a "couple." This quantity can be measured in units of newton metres or joules per radian. It can be defined as the cross product of (*) displacement and force, or the time derivative of angular momentum. It is also known as "moment." For 10 points, name this measure of how much a force acting on an object causes it to rotate.
In mechanics, Varignon's theorem deals with this quantity. When a system of forces has a nonzero value for this quantity but no resulting force, it is called a "couple.
{torque} [or moment before it is read]