Engineering Board Exam Reviewer · Applications: Cooling, Heating, and Mixture Problems · hard

Water flows into a tank according to dV/dt=k(50-V) with V(0)=0 and k=0.1. Find the volume after 10 minutes.

  1. 31.6
  2. 36.8
  3. 45.0
  4. 25.0

Answer

A. 31.6

Solution

V=50(1-e-kt)=50(1-e-1) 50(0.6321) 31.6.

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