{"id":56932,"date":"2025-12-08T05:07:51","date_gmt":"2025-12-07T20:07:51","guid":{"rendered":"https:\/\/phys-edu.net\/wp\/?p=56932"},"modified":"2025-12-08T05:07:51","modified_gmt":"2025-12-07T20:07:51","slug":"the-100-yen-toy-that-makes-invisible-sound-and-earthquakes-visible","status":"publish","type":"post","link":"https:\/\/phys-edu.net\/wp\/?p=56932&lang=en","title":{"rendered":"The 100-Yen Toy That Makes Invisible Sound and Earthquakes Visible"},"content":{"rendered":"

Science Trainer, Ken Kuwako. Every Day is an Experiment.<\/span><\/p>\n

Have you ever actually seen sound? Of course, sound itself is invisible. However, in science classes, we put a lot of effort into finding ways to make this unseen world of sound “visible.” This time, I’d like to introduce a surprising secret weapon that plays a major role in a middle school first-year lesson on the “nature of sound.” It\u2019s an everyday toy that almost everyone has played with at least once.<\/p>\n

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Physics is Built on “Things” and “Events”
\nThe field of physics can be broadly divided into two aspects. One is “Things” (Mono), which deals with the movement of particles. This includes the area of “Mechanics,” such as throwing a ball or a car driving. Since these have shape and are visible, they are easy for students to visualize and are familiar topics.<\/p>\n

The other is “Events” (Koto), or phenomena. The main actor here is the “Wave.” This phenomenon is not about matter itself moving, but about “the transfer of energy or vibration.” This concept isn’t covered in much depth before middle school, so when students first encounter the idea of a “wave,” many struggle to form a mental picture of it.<\/p>\n

That’s why, a few years ago, I introduced an experiment using a toy spring (a Slinky) to help students grasp these “invisible waves.”<\/p>\n

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Slinky (Amazon)<\/a><\/p>\n

A 100-Yen Toy Over 5,000-Yen Lab Equipment
\nThis toy spring is actually one of the most powerful tools in science education. Because you can get it at a cheap candy store or a 100-yen shop, it\u2019s very inexpensive. School budgets can afford to purchase one for every student, or at least one for every two students.<\/p>\n

Of course, the science lab has impressive “educational springs” that cost around 5,000 yen each. These are good because they have a decent weight, and the waves travel slowly, making them easy to observe. However, because they are expensive, we can’t buy many, and the lesson often ends up as a simple demonstration experiment shown by the teacher at the front of the room.<\/p>\n

The learning effect is far greater when “each student gets to hold the spring in their own hands and create the waves themselves.”<\/p>\n

Experiencing “Transverse Waves” and “Longitudinal Waves”
\nWhen students hold the spring, they naturally start learning about the nature of waves just by playing with them.<\/p>\n