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Bodies In Motion

Newton's 1st and 2nd laws of motion
Newton's First Law of Motion states that a body at rest will remain at rest unless an outside force acts on it, and a body in motion at a constant velocity will remain in motion in a straight line unless acted upon by an outside force.

The Second Law of Motion states that if an unbalanced force acts on a body, that body will experience acceleration ( or deceleration), that is, a change of velocity.

Figure 1.
Circular Motion
Click on the image to view the animation. The ball is connected to a string which is connected to the center of the circle. In the animation the string breaks as the ball reaches the top of the circle.

The important thing to notice in this animation is that the ball continues in the direction it is going when the string breaks (direction A) rather than in the direction of the "centrifugal force" (direction B).