10. One end of a 1.5 kg uniform stick that is 2.0 m long is placed against a vertical wall as shown. A light cord making an angle 0 with the stick holds the other end. The coefficient of static friction between the end of the stick and the wall is 0.500. a) What is the maximum value the angle 0 can have if the stick is to remain in equilibrium? Ө b) When 0 = 15° a body of the same weight as the stick is suspended from the stick a distance x from the wall. What is the minimum value of x for which the stick will remain in equilibrium?

1. ch A uniform 40.0-kg scaffold of length 6 m is supported by two light cables, as shown below. An 80 kg painter stands 1 m from the left end of the scaffold, and his painting equipment is 1.5 m from the right end. The tension in the left cable is twice that in the right cable. Find 1. The tension in the left cable = 2. The tension in the right cable = 3. The mass of the equipment = N 99+ N kg Think & Prepare 1. If the plank is in equilbrium, torque about any point will be zero. Pick a point about which to calculate torques. 2. Draw all forces and torques. 3. Write down the First Condition for Equilibrium symbolically. 4. Write down the Second Condition for Equilibrium symbolically. 5. How many unknowns are there? How many equations are there? 6. How can you solve the equations find the unkowns?

11. The diagram below shows a ladder that is 6.0 m long and has a mass of 20.0 kg. The ladder rests on a level floor and against a wall at an angle of 15° to the wall. The coefficient of static friction between the ladder and the floor is 0.232. A person with a mass of 60.0 kg begins to climb the ladder. The base of the ladder will begin to slide away from the wall when the person reaches which distance interval from the base of the ladder? A. 0 m–1.5 mB. 1.5 m–3.0 mC. 3.0 m–4.5 mD. 4.5 m–6.0 m

Q18