A transducer - a small box that produces sound waves - on the bottom of the glass forms an acoustic wave that suspends the bubble in the water.
(a small box; produces; sound waves) (A transducer; forms; an acoustic wave that suspends the bubble in the water) (an acoustic wave; suspends; the bubble in the water)
a small box A transducer an acoustic wave
produces forms suspends
sound waves
an acoustic wave that suspends the bubble in the water
the bubble in the water