Static Equilibrium

1. Identify the object of interest. 2. Draw a free-body diagram. 3. Choose a coordinate system. 4. Write out Newton's 2nd law for each component of the coordinate system. 5. Choose a pivot point. 6. Write out the torque equation using  for clockwise torque and + for counter-clockwise torque. 7. Solve system of equations for unknown values.

Grocery Sign A grocery store sign has a mass of 50 kg and is centered on a 8 kg rod which is 2.0 m long. What is the tension in the support wire, and the force exerted by the wall on the rod? Jordans Grocery 30°

Up the Ladder A 4.0 m long ladder is placed against a very slick wall at an angle of 60° with respect to the floor. The coefficient of friction between the ladder and the floor is How far up the ladder can a 60 kg person go before the ladder begins to slip?

Race Down the Slope A block and a ball move down an inclined plane. The block is able to slide while the ball has enough friction to roll. What are the velocities when they reach the bottom of a 0.25m high slope assuming frictional loses are negligible?

At the Arcade An 8.0 kg bowling ball is rolled from x=6m to the left. What velocity is required to get it to x=1m? How high is the hump? Where will the ball end up in the future? Where are the turning points if the ball is at x=1m with 20 J of energy?

Stability Determine stability through the potential energy function. UnstableStableNeutral Equilibrium Height vs. Position Potential Energy (J) Position (m)

Classify Stability How would your classify the following? (Stable, Unstable, Metastable, Neutral)