Newton’s first law of motion says that an object at rest will remain at rest unless acted on by an unbalanced force. An object in motion continues in motion with the same speed and in the same direction unless acted upon by an unbalanced force. What does this mean, in plain english? Every object in the universe hates change: If it’s stationary, it will not just start moving by itself. If it is moving, it won’t change that movement by speeding up, slowing down, or changing direction. Not ever. If these things DO happen, it’s because some force was applied on the object that MADE it changes its motion. This isn’t necessarily obvious to common sense, by the way, but that’s only because here on Earth, with all the gravity and friction and air resistance, there are always forces acting on a moving object.
Written by Allen Versfeld