Directions: Use the words in the word box to complete the following sentences.
 acceleration
 gravity
 counteract
 resistance
 balanced
 force
 When the forces acting on an object are _______________ , there is no change in the object's motion.
 A _________________ acting on a resting object can cause the object to move.
 On Earth, __________________ pulls all objects toward the ground.
 When a force acts in the opposite direction of another force, the forces ______________ each other.
 More than one force acting on a falling object can reduce its downward ____________________.
 Air _____________________ is caused by molecules of air pushing against a moving object.