How is the motion of an object affected when a force acts on it?

Newton's first law of motion is sometimes called the law of inertia. When the forces acting on an object are balanced, the object is either at rest or moving with a constant velocity. Unbalanced forces can cause an object to accelerate or decelerate. Unbalanced forces can also cause an object to change direction.

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what best describes physical development during adolescence is the development of secondary sex characteristics happens at a rate unique to each individual.

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