... of a 3D-body

By applying equilibrium to the free-body diagram of a body you can find unknown forces and moments which prevent motion (translation and rotation). The concept of equilibrium of a body is treated in chapter 3.1.1 of the book Engineering Mechanics Volume 1 Hartsuijker & Welleman, 2006. At maximum six unknown forces can be solved in a threedimensional problem. The steps involved are:

1. Draw a free body diagram of the body
2. Split the forces in convenient directions by applying resolution of forces
3. Solve the forces and moments using $\sum F = 0$ in three nonparallel convenient directions and ${\left. {\sum T } \right|_{xy}} = 0$ for any arbitrary line $xy$ as treated in chapter 3.3.2 of the book Engineering Mechanics Volume 1 Hartsuijker & Welleman, 2006. The full procedure is shown in chapter 3.4.

Exercises¶

• If you’re a TU Delft student, you can practise with the following exercises on threedimensional problems.