Can't view YouTube? Download MP4 Challenge Question: Why does
the amount of water on the speakers affect how often droplets
are ejected? Challenge Answer: The more water, the larger the
surface area of the sphere of water. The speakers exert a force
on the sphere of water, increasing the pressure inside the
sphere. Pressure is F/A, so a given sound will generate a lower
pressure in the sphere. If the pressure per unit area is strong
enough to overcome the surface tension of the water, a droplet
is ejected. Therefore, more water means larger surface area,
which means lower force per unit area on a water droplet.
Challenge Winner: Zach Mitchell from Chapel Hill, NC