Do Force Diagrams Show Forces Exerted by the Object?

[catenn]

Hi, I have had a slight confusion on the Force and Free-Body Diagrams. I know that they are represented by arrows for the vectors in the direction of the force and that forces exerted on the object are shown. Are the forces exerted by the object also shown for the Force and Free-Body Diagrams? Or is there also a difference from one showing and the other not? Thanks!

 

[Andrew Mason]

Hi, I have had a slight confusion on the Force and Free-Body Diagrams. I know that they are represented by arrows for the vectors in the direction of the force and that forces exerted on the object are shown. Are the forces exerted by the object also shown for the Force and Free-Body Diagrams? Or is there also a difference from one showing and the other not? Thanks!

A free-body diagram is a graphical picture that shows the body and all the forces (in vector form) that act on that body. The net force (vector sum of all those forces) gives you the mass x acceleration of the body.

You only show the forces acting on the body. If the body is exerting a force on another body, Newton's third law requires that other body to be exerting an equal and opposite force on it, so you would show that force in your diagram.

AM