Question

When doing frames and machines and we split into FBD of different members its important to remember

a) Only external forces matter
b) Internal forces are negligible
c) Only consider gravitational forces
d) Include both internal and external forces

Answer 1

When analyzing frames and machines, it is crucial to include both internal and external forces in the free-body diagrams to accurately apply Newton's second law for proper analysis of motion and internal stresses.

Step-by-step explanation:

When studying frames and machines and splitting them into free-body diagrams (FBD) of different members, it's essential to remember to include both internal and external forces. Internal forces are the forces that the parts of the structure exert on each other, and external forces include all forces acting from outside the system.

For accurate analysis using Newton's second law, we need to consider the correct forces acting on the system. While it is true that only external forces affect the motion and thus, are included in the FBD, the internal forces must not be deemed negligible as they help understand the internal stresses and potential points of failure within the machine or frame.

The key to proper analysis is identifying the system of interest and distinguishing between internal and external forces. By doing this, we can solve complex problems efficiently by focusing on the significant factors that affect the motion of the system.