Concept explainers
You’ve been hired by your state’s environmental agency to monitor carbon dioxide levels just above rivers, with the goal of understanding whether river water acts as a source or sink of CO2. You’ve constructed the apparatus shown in Fig. 12.38, consisting of a boom mounted on a pivot, a vertical support, and a rope with pulley for raising and lowering the boom so its end can extend different distances over the river. In addition, there's a separate rope and pulley for dropping the sampling apparatus so it’s just above the river.
FIGURE 12.38 Passage Problem 64–67
If you pull the boom rope with constant speed, the angle the boom makes with the horizontal will
- a. increase at a constant rate.
- b. increase at an increasing rate.
- c. increase at a decreasing rate.
- d. decrease.
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