Water Rocket Calculator

Launch Gauge Air Pressure psi
PreLaunch Tank
Air Volume
Nozzle Diameter cm
Rocket Diameter cm
Mass of Empty Rocket grams
Volume of Empty Fuel Tank liters
Air Friction Constant -
Air Friction Velocity Exponent -
Air Density lb/ft3
Barometric Pressure hPascal
Burnout Time sec
Burnout Velocity m/sec
Burnout Height meters
Average Blastoff Acceleration m/sec2
Maximum Blastoff Acceleration m/sec2
Max Rocket Altitude meters
Time to Max Altitude sec
Select Data
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spreadsheet Column
This calculation is based on an algorithm and formulas in the March 1995 Physics Teacher, Volume 33, Number 3, p 150-157: Soda-Bottle Water Rockets by David Kagan, Louis Buchholtz and Lynda Klein. Note that for small values of "Launch Gauge Pressure", the calculation may use the square root of a negative number - a "NaN" (not-a-number) to the Javascript interpreter. Just raise the pressure value and this problem should go away.

This model was modified to include friction effects using: