3. Force and Moment Equilibrium

Try these first

1. 1.

   What condition must be met for an object to be in translational equilibrium?

   Hint

   Consider what it means for forces to cancel each other out.

2. 2.

   Define rotational equilibrium.

   Hint

   Think about what keeps objects from rotating.

3. 3.

   What condition must be met for an object to be in translational equilibrium?

   • Sum of forces = 0
   • Sum of forces > 0
   • Sum of forces < 0

   Hint

   Think about what happens when forces push on an object.

4. 4.

   In rotational equilibrium, what must the sum of moments equal?

   • True
   • False

   Hint

   Consider what prevents an object from rotating.

5. 5.

   A seesaw is perfectly balanced when a 30 kg child sits 2 m from the center on one side. How far must a 45 kg child sit on the other side to maintain equilibrium?

   Hint

   Set up an equation based on the principle of moments.

6. 6.

   A beam is supported at one end and has a load of 200 N located 3 m from the pivot. Calculate the moment exerted about the pivot.

   Hint

   Apply the formula for calculating torque.