Unbalanced forces
a
make an object move opposite the applied force.
b
maintain the constant motion of an object.
c
cause the motion of an object to change.
d
can change an object's speed but not direction.
c
cause the motion of an object to change.
Unbalanced forces are those that cause a change in the motion of an object, which can be a change in its speed or direction of movement (or both). According to Newton's first law of motion, an object will remain at rest or in uniform motion in a straight line unless acted upon by an unbalanced force.