A Simple Exponential Model in the Time of Covid

The app below shows an example of exponential growth: you will learn how to create a simple mathematical model for a culture of bacteria. Explore it, using buttons and sliders. (Note: The doubling time of a population exhibiting exponential growth is the time required for a population to double, given that the population will always take the same amount of time to double.)

A bacteria culture doubles in number every hour. The expression gives the number of bacteria in the culture after h hours. (a) What does the constant coefficient 112 mean? (b) What does the base 2 of the exponential term mean? (c) How many bacteria are there after 3 hours?

Now try it yourself...