18.1.2. Unstable Equilibrium

Try these first

1. 1.

   What is stable equilibrium?

   Hint

   Think about objects that can easily right themselves.

2. 2.

   Give an example of unstable equilibrium.

   Hint

   Consider how easily it can be knocked over.

3. 3.

   What happens to a system in unstable equilibrium when disturbed?

   • It returns to equilibrium
   • It stays in place
   • It moves away from equilibrium

   Hint

   Consider how easily disturbed objects behave.

4. 4.

   True or False: A marble on a flat surface is an example of stable equilibrium.

   • True
   • False

   Hint

   Think about what happens when you push it.

5. 5.

   Derive the moment equation for a rigid bar connected to a spring at different angles. Discuss how this affects stability.

   Hint

   Use trigonometric identities to facilitate your derivation.

6. 6.

   Assess a scenario where an engineered structure falls due to unstable equilibrium. What could have been done to prevent it?

   Hint

   Reflect on real-world examples of structural failures.