Water flows through a -meter section of pipeline carrying a contaminant whose…

MATHEMATICS · Multi-part · AP · Calculus AB · Limits and Continuity · Limits and Continuity

Problem

Water flows through a 300300-meter section of pipeline carrying a contaminant whose concentration varies along the pipe. The concentration C(x)C(x), in milligrams per liter, at a point xx meters from the pipe’s entrance satisfies C(0)=0.20C(0)=0.20 and C(300)=0.60C(300)=0.60. Engineers know that concentration changes smoothly along the pipe. (1) Environmental regulations require a warning sign wherever the concentration first reaches 0.45 mg/L0.45\text{ mg/L}. Prove that at least one such point exists inside the pipe. (2) Explain whether the information given is sufficient to conclude that there is a point where the concentration is exactly 0.50 mg/L0.50\text{ mg/L} and located no more than 200200 meters from the entrance. (3) Sensors are to be installed no more than DD meters apart so that the data they collect will guarantee detection of every concentration between 0.20 mg/L0.20\text{ mg/L} and 0.60 mg/L0.60\text{ mg/L} at some sensor. Determine an upper bound for DD and justify your answer.

Related theory

Browse the problem library