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- Draw a picture of the situation and a force diagram of all the forces for
each body (a
**free body diagram**).- In the force diagram for each object, include only the forces acting on that object.
- The force exerted by a rope is called the tension and usually denoted .
- The contact force exerted by a surface is called the
**normal force**and always acts perpendicular to the surface.

- Set up a coordinate system and apply Newton's second law:

*F*_{x}=*ma*_{x},*F*_{y}=*ma*_{y}. - If necessary, use the kinematic equations of motion to solve for the desired quantities.

10/9/1997