A devastating tornado

How to make a tornado in a bottle

Safe­ty pre­cau­tions

None.

Equip­ment

  • glass bot­tle;
  • wa­ter;
  • bowl.

Step-by-step in­struc­tion

Take a bot­tle of wa­ter, turn it up­side down, and pour the wa­ter into the bowl. Note that the wa­ter flows slow­ly and fit­ful­ly. Re­peat the ex­per­i­ment, swirling the bot­tle be­fore be­gin­ning to pour. Note the for­ma­tion of a “tor­na­do” fun­nel and the rapid flow of wa­ter.

Process de­scrip­tion

When we turn the bot­tle over, wa­ter wants to leave the bot­tle, while air wants to en­ter. The wa­ter’s flow is in­ter­rupt­ed by air bub­bles try­ing to en­ter the bot­tle. When the bot­tle is spun, the re­sult­ing cen­trifu­gal force push­es the wa­ter against the walls. The ef­fect is en­hanced when we open the bot­tle. An air chan­nel is cre­at­ed in the cen­tral “axis” around which the liq­uid vor­tex ro­tates. As a re­sult, the wa­ter leav­ing and air en­ter­ing can oc­cur in par­al­lel. The stream be­comes un­in­ter­rupt­ed, let­ting the wa­ter flow faster.