QCEVault

Differential equations and related rates — Question 230

Original QCE Vault practice · 6 marks

Q230 · Practice questionTechnology-freeComplex familiar6 marks

QUESTION 230 (6 marks)

A well-mixed 100 L aquarium tank receives solution at 10 L/min with concentration 0.4 g/L. Mixture leaves at the same rate. Initially the tank contains pure water. Let S be salt mass in grams.
A well-mixed tank of fixed volume 100 L. Inflow is 10 L/min at 0.4 g/L; outflow is 10 L/min with concentration S/100 g/L.
a)
Form and solve the differential equation.
[3 marks]
b)
Find limiting concentration and first time concentration reaches 0.2 g/L.
[3 marks]
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