The “Blower” app is available for two dollars ($1.99) in the app store. Blower, as the name suggests, transforms your smartphone into a powerful blower. Literally. But how does the app enable a smartphone to blow enough air to blow out birthday candles?
How Can a Smartphone Blower App Blow Out Birthday Candles?
In a new video, YouTube channel The Action Lab takes a scientific look at the phenomenon. When the Blower App is activated, it displays a fan on the screen that spins and whirls as it blows on objects.
It’s powerful enough to extinguish a few candles. It’s not, however, a fan-like stream of air blasting from your phone.
James Orgill of Action Lab demonstrates the physics behind how this app (and others like it) work in this video; the gimmick, of course, is oscillating sound waves. At your next family holiday meal, it could be a fun party trick — and a diversion from avoiding political talk.
The channel’s host demonstrates how the Blower app can use a smartphone’s speakers to blow out candles in the video above.
But, while the physics behind the ability appears straightforward—we blow out candles all the time, so it’s no big deal—the nuances are fascinating. Also, it’s counterintuitive.
While a smartphone’s speaker cones blow and suck on surrounding air, creating vibrations in the air and thus sound waves, the amount of air the speakers blow out and suck in is exactly equivalent, according to the channel’s host.
How Does the Smartphone Manage to Extinguish Candles?
As the channel’s host explains, the Blower app works because of the inherent nature of a speaker. Even though speakers suck in and blow out the same amount of air, the way they suck and blow differs, according to the host.
When a speaker cone suckes in air, it does so in an unfocused manner from all around it. When it blows out air, on the other hand, it does so in a way that creates a “column” of sorts. This directed column has enough force to blow out a birthday candle, for example. Or teeny-tiny specks of dust.
The frequency of sound waves generated by a smartphone’s speakers is also important. 240 hertz is the sweet spot for producing the best blow with a smartphone’s speakers, according to the Action Lab host.
