Following the definition of work written above we see that work done (W) by a constant force (
This means work is scalar product of two vectors quantities. So work is a scalar quantity.
When force is applied to rotate a body around an axis the magnitude of rotational effect caused by the force depends on three quantities (1) the distance of point of application of force from axis of rotation,the magnitude of radius vector (
Magnitude of Torque
So vectorially it is the cross product of two vectors
So torque is a vector quantity. The direction of torque is determined by the thumb rule as shown in above figure.