would be smaller than 4.3 m, however, the formula would give you an exact answer. The reason that the small nozzle had a lower eruption height than the medium nozzle is that the opening was too small. Each eruption lasts for the same amount of time because the conditions are the same; the aspartame in the coke reacts with the mentos, which causes pressure that leads to an eruption. When the nozzle size was decreased, it created more pressure, which is why the eruption height rose between the bottle with no cap and the medium cap. However, once the small cap was put on the geyser tube, the pressure was higher, but there was just not enough pressure to push the coke out of the small opening any faster. A possible experiment for the future is testing different size nozzles to see which nozzle size allows for the highest eruption before the opening is too small.
4 References 1. Tonya Coffey, American Journal of Physics, Volume 76, number 6, pages 551-337 (2008). 2. Holly Aery and Adam Sierzputowski , Eruptions Caused by Mentos Increase in Height with Smaller Nozzle Sizes , Volume 1, number 5, pages 23-26(2008). [page 2 and 4 of this paper] 3. Gabriella Necklas and Kierstin Wall, Creating a “Misting Mentos Eruption,� number 8, pages 21-22(2008). [page 2 and 4 of this paper]
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