Question
Let y(t) denote the mass of a radioactive substance at time t.t. Suppose this substance obeys the equation
y′(t)=−14y(t).
Assume that, initially, the mass of the substance is y(0)=M>0. At what time does half of the mass remain? (Round your answer to 3 decimal places).
PLease explain
y′(t)=−14y(t).
Assume that, initially, the mass of the substance is y(0)=M>0. At what time does half of the mass remain? (Round your answer to 3 decimal places).
PLease explain
Answers
Steve
this is just like the other one. You already know about radioactive decay, and how it is an exponential function, right?
Sarah
Yes but I'm not sure what the m>0 is for
Steve
surely the initial mass is positive. Kind of makes things more real.
Looking at the original equation, if y(0) < 0, we have exponential growth, not decay.
Looking at the original equation, if y(0) < 0, we have exponential growth, not decay.