1. Forces and Equilibrium

Question 1

Define:

• External force
• Internal force

Answer 1

• External force: acting on the body (e.g. gravity, other objects)
• Internal force: acting between different parts of the body (forces bewteen subsystems, e.g. engine in car).

Question 2

What is meant by Statics?

Answer 2

Statics are presetnt when an object or system has no acceleration, both in translation and rotation

Question 3

What are the three conditions for equilibrium?

Answer 3

• Vertical forces in equilibrium (resultant vert forces = 0)
• Horizontal forces in equilibrium (resultant horz forces = 0)
• Moment forces in equilibrium (resultant moment forces = 0)