What Is the Long-Term Behavior of Radioactive Substance Mass Q(t)?

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Homework Statement


A process creates a radioactive substance at the rate of 2 g/hr and the substance decays at a rate proportional to its mass, with constant of proportionality k=0.1(hr)^-1. If Q(t) is the mass of the substance at time t, find the limit of Q(t) as t approaches to infinity.

Homework Equations


None.

The Attempt at a Solution


I know how to take the limit of Q(t) but I need to solve for Q(t) first. And I tried to find it but don't know the formula to solve for Q(t).
 
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Math10 said:

Homework Statement


A process creates a radioactive substance at the rate of 2 g/hr and the substance decays at a rate proportional to its mass, with constant of proportionality k=0.1(hr)^-1. If Q(t) is the mass of the substance at time t, find the limit of Q(t) as t approaches to infinity.

Homework Equations


None.

The Attempt at a Solution


I know how to take the limit of Q(t) but I need to solve for Q(t) first. And I tried to find it but don't know the formula to solve for Q(t).

Set up a differential equation for Q(t). Solve it.
 
Math10 said:

Homework Statement


A process creates a radioactive substance at the rate of 2 g/hr and the substance decays at a rate proportional to its mass, with constant of proportionality k=0.1(hr)^-1. If Q(t) is the mass of the substance at time t, find the limit of Q(t) as t approaches to infinity.

Homework Equations


None.

The Attempt at a Solution


I know how to take the limit of Q(t) but I need to solve for Q(t) first. And I tried to find it but don't know the formula to solve for Q(t).
You aren't "solving" for Q(t) -- you have to take the given information in the problem and write a differential equation that involves Q(t) based on that information.
 
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