Free-body diagrams

It might help if you call these "one-body diagrams." The idea is to draw a single object, show all the forces acting ON it, and label each force.

For example, consider Bob and Jane: they are trying to slide a heavy box across the floor, but it isn't working: the box doesn't move at all.

Draw a diagram showing only the box. Draw an arrow for each force acting ON the box, showing roughly the direction, size and location of each force. Make a table like this, listing all the forces and indicating the x and y components of each one. What is the total force in each direction?

   force        x            y
  --------------------------------
           |          |         
           |          |         
           |          |         
           |          |         
           |          |         
           |          |         
           |          |         
  --------------------------------
   total   |          |
  --------------------------------

Now draw another freebody diagram, this time for Bob. Make another table to show the components of all forces acting on him.