Michiel Postema: Why my daughter wants me to buy her a €40 pair of flip flops

“The other day my daughter asked me for €40 to buy flip flops. I did buy a pair but not for my daughter, but for science,” Postema says at the beginning of his lecture.
In this lecture, Postema shows examples of what ultrasound can be used for. The applications of ultrasound range from pushing particles through cell membranes to investigating viscoelastic materials, which as it so happens also include flip flops.
A brief demonstration is given on medical ultrasound using a sauna bucket and a pair of flip flops submerged in it. The experiment shows that flip flops are a perfect acoustic damping material.
“The flip flop is one of the most baffling and versatile acoustically responsive media in the known universe, so I do understand why my daughter needs a pair,” Postema says.
In line with sonic tradition, Postema concludes with “Piezo be with you!”