Unbalanced forces
a
maintain the constant motion of an object.
b
cause the motion of an object to change.
c
can change an object's speed but not direction.
d
make an object move opposite the applied force.
b
cause the motion of an object to change.
An unbalanced force acting on an object results in a change in the object's motion, which can include a change in speed, a change in direction, or both. According to Newton's second law of motion, the net force acting on an object is equal to the mass of the object multiplied by its acceleration (F = ma). This means that if the net force (or unbalanced force) is nonzero, the object's velocity (including both speed and direction) will change.