Since fluid is pumping in and out at the same rate (5L/min), the total fluid volume in the tank stays constant at 350L. Only the amount of salt and its concentration changed overtime.

Let A(t) be the amount of salt (g) at time t and C(t) (g/L) be the concentration at time t

A(0) = 10 g

Brine with concentration of 1g/L is pouring in at the rate of 5L/min so the salt income rate is 5 g/min

The well-mixed solution is pouring out at the rate of 5L/min at concentration C(t) so the salt outcome rate is 5C g/min

But the concentration is total amount of salt over 350L constant volume

C = A / 350

Therefore our rate of change for salt A' is

A' = 5 - 5A/350 = 5 - A/70

This is a first-order linear ordinary differential equation and it has the form of y' = a + by. The solution of this is

$y = ce^{bt} + \frac{a}{b}$

So $A = ce^{\frac{-t}{70}} + \frac{5}{1/70} = ce^{-t/70} + 350$

with A(0) = 10

c + 350 = 10

c = 10 - 350 = -340

$A(t) = -340e^{-t/70} + 350$

4 0

3 years ago

Why do polar compounds tend to have higher melting points than nonpolar compounds

I am Lyosha [343]

Answer:

The inter-molecular forces holding non-polar compounds together is low compare to that of polar compounds. Therefore, it will take less energy to break the bond for non-polar compounds and vice versa. That is why polar compounds have higher melting points than non-polar compounds.

Explanation:

5 0

3 years ago

Which type of ooze dominates in warm shallow ocean floors?<br>A. Calcareous<br>B. Silieous

gogolik [260]

Actually it's sediment

6 0

4 years ago

một ngẫu lực có momen không đổi M=10KNm tác dugj lên tang của một trục tời xem là đĩa tròn đồng chất có bán kính R =30cm và có t

Amanda [17]

Can you speak English pls?

5 0

3 years ago