College Physics with MasteringPhysics 7th Edition by Jerry Wilson,Anthony Buffa,Bo Lou

تمرين 96

To haul a boat out of the water for the winter, a worker at the storage facility uses a wide strap with cables operating at the same angle (measured from the horizontal) on either side of the boat (Fig.). (a) As the boat comes up vertically and decreases, the tension in the cables (1) increases, (2) decreases, (3) stays the same. (b) Determine the tension in each cable if the boat has a mass of 500 kg and the angle of each cable is 45° from the horizontal and the boat is being momentarily held at rest. Compare this to the tension when the boat is raised and held at rest so the angle becomes 30°.

FIGURE Hoist it up See Exercise.