[Ed Law]

Hi Jesse,

I like your spreadsheet. Very cool. A number of questions and suggestions.

Instead of asking the user to enter wind resistance which is hard to estimate, you can calculate it. It is based on diameter of ball, coefficient of drag (shape constant) and density of air. Also since you are asking the user to enter number of spinning shooter sides, if it is only 1, it will create top spin or back spin. Based on my spreadsheet calculation, that can affect the trajectory quite a bit depending on weight to diameter ratio of the ball. Ask a tennis player and you will see.

A question for you. Do you take into account the speed of motor when it is under load or are you using free speed? From your experience, how much difference is there?

I am going to show your spreadsheet to my son. He is doing science olympiad this year and he will be doing the trajectory challenge. Your spreadsheet will be very useful for him. Thanks.

Ed Law