# Monthly Archives: December 2020

## BB Ballistic Coefficients

A number of years ago, I was asked by a father to assist him and his son with a science project that involved calculating the ballistic coefficient of a BB gun projectile. I provide dthis father-son duo with the required calculations (documented here) and the answer I obtained seemed reasonable. Continue reading

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## Optimized Piecewise Linear Model Using Excel

I was recently asked to create a piecewise linear model for a rather complex battery discharge curve, which is a type of task that I have performed dozens of times. I was told to perform this task in Excel because that is the only computation tool that this customer uses. I normally do this task in R because I like the segmented package, however, Excel does a very good job with the task, especially if you use the Solver add-in to "tune" the model. Continue reading

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## US WW2 Torpedo Production Chart Using Power Query

During my readings on the Pacific War, I often see the chart shown in Figure 1. I decided to do a bit of digging and find the source data for this chart in the hope of making a version of this chart that is a bit clearer and easier to use. Continue reading

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## 18% of American's Can Determine 52 Senators?

I was listening to a podcast this week where I heard James Carville state that "18% of American's can determine 52 senators." I thought this was an interesting quote that I could have the students I tutor verify using Excel and Power Query. All of the data is available online and the problem has a relatively short solution. Continue reading