Net torque is the sum of all the individual torques acting on an object. Torque measures how much rotation-causing force is acting on an object. If the sum of all the torques is zero, the object is in rotational equilibrium.
To calculate torque, a pivot point must be defined. The distance between the pivot point and the force's acting point is called the moment arm. Torque is the cross product between the force vector and the moment arm vector. The right-hand rule helps determine which direction the torque vector points. The fingers of the right hand are pointed in the direction of the moment arm and are curled towards the force vector; wherever the thumb is pointing is the direction of the torque vector. The SI measurement unit of torque is a Newton-meter.