according to newton's second law , the net force on an object is the product of mass and the acceleration of the object. The formula is given as
[tex]F_{net}[/tex] = m a
where m = mass of the object and a = acceleration of the object.
when an unbalanced force acts on an object , there is a net force acting on the object and hence the object accelerate as a result.
hence the object accelerate in the direction of net force.