How fast can a water rocket can go?
Posted: Fri Aug 12, 2016 8:03 am
I would like to know how fast can a water rocket go?
barrosla,
That is an interesting question. Unfortunately it is one that is difficult to answer because it depends on many different factors, such as bottle size, weight, fuel type and amount, how much pressure you put into it, and several more.
The short answer is that initial velocity is based on acceleration multiplied by the amount of time to expend the fuel.
I've developed a power point slide show that discusses bottle rockets and from slide 11 on runs through how to calculate the performance of a water bottle rocket with initial velocity being calculated on slide 19. This is a presentation I developed for a 5th grade science class, so slides 1 to 10 discuss how rockets work and stuff. The videos are not attached (to big) so they won't play. The calculations are for an example 2 liter rocket filled with 0.7 liters of water and pressurised to 40psi.