Finding Interference in the Real World (April 2019) by KEIO FUTURELEARN https://padlet.com/fl_keio/rbhwcruhm1tf If you know what you're looking for, you'll often see evidence of interference in the real world. It might be light, or sound, or waves in a pond or the ocean. Find an example, and post a photo or video here. Describe what you found. en-us 2019-03-24 09:20:32 UTC 2025-04-24 11:48:07 UTC hello@padlet.com https://padlet-assets.s3.amazonaws.com/icons/Rocket.png https://padlet.com/fl_keio/rbhwcruhm1tf/wish/347093415 This is one of a series of paintings by artist Tanya Gravening - showing art and science can happily co-exist!]]> 2019-04-01 10:19:19 UTC https://padlet.com/fl_keio/rbhwcruhm1tf/wish/347093415 Manipulated Standing Air Waves cheewai1972 https://padlet.com/fl_keio/rbhwcruhm1tf/wish/347308881 I do love these types of videos! The sound waves are adjusted so they create standing waves where they can levitate small particles at the nodes of the 3D standing waves. Physics Girl explains it in this other video - https://youtu.be/ABjRnSYw-4k]]> 2019-04-01 17:34:14 UTC https://padlet.com/fl_keio/rbhwcruhm1tf/wish/347308881 https://padlet.com/fl_keio/rbhwcruhm1tf/wish/347731685 I think these are cool and meditative!]]> 2019-04-02 17:00:36 UTC https://padlet.com/fl_keio/rbhwcruhm1tf/wish/347731685 Why the bass behaves differently https://padlet.com/fl_keio/rbhwcruhm1tf/wish/348740390 This is not a very obvious one, but interference has a very deep effect on the conventions in musical composition.
As the musical pitch increases, the frequency of the sound increases exponentially. That means that tones in the bass range have closer frequencies than higher sounds, so they are more likely to produce perceivable interference, which sounds "dirty." Because of that, there are conventions in music that aim at avoiding it. For example, striking full chords on an acoustic guitar is very common, but not on the bass guitar, and definitely not in the lowest registers. Similarly, it's rare to hear two or more notes played simultaneously on the lowest registers of the piano or the organ that are not an octave apart (which means the high note has double the frequency of the low one). In classical music, double basses often play the same thing as the cellos, only an octave lower. In general, while mid-range and high tones can be close together, the bass sounds have to stay far apart.

Below, I have an example of what happens when these conventions are broken and the basses get close together. The three singers have extremely low voices (basso profondo). When they sing solo, they all sound very clear, but when they sing in harmony, the sound often becomes distorted because of the interference (e.g. 0:29-0:41).
https://www.youtube.com/watch?v=W0HmIYv51pc&list=PLzp0fvxpl2QyvOnApVHQ4U-kjduHCYAa_ 

]]> 2019-04-04 22:02:00 UTC https://padlet.com/fl_keio/rbhwcruhm1tf/wish/348740390 https://padlet.com/fl_keio/rbhwcruhm1tf/wish/349094000 2019-04-05 22:06:40 UTC https://padlet.com/fl_keio/rbhwcruhm1tf/wish/349094000 How clear water droplets can be made iridescent https://padlet.com/fl_keio/rbhwcruhm1tf/wish/349234329 Engineers at MIT and Penn State University have found that, under certain conditions which exploit light wave interference effects, ordinary clear water droplets can be made to produce brilliant colours. ]]> 2019-04-07 10:59:12 UTC https://padlet.com/fl_keio/rbhwcruhm1tf/wish/349234329 Interference in the Real World may be found in the radio waves. Radio waves have frequncies. When we transmit a signals it may be some harmonics frequencies and such frequencies may interfere with other radio frequencies and these harmonics frequencies are not sporadic but there are rules of each harmonic frequency. sp4wrf https://padlet.com/fl_keio/rbhwcruhm1tf/wish/354388383 2019-04-26 09:28:51 UTC https://padlet.com/fl_keio/rbhwcruhm1tf/wish/354388383 TK2053 ravie https://padlet.com/fl_keio/rbhwcruhm1tf/wish/356465314 2019-05-03 02:47:28 UTC https://padlet.com/fl_keio/rbhwcruhm1tf/wish/356465314 Interference on ice https://padlet.com/fl_keio/rbhwcruhm1tf/wish/359366544 I found two interference examples related to ice:
1. Interference in ice hockey - https://www.nhl.com/video/what-is-interference/t-277440360/c-49798903
2. The second one is related to the light reflection from ice crystals: 
https://www.osapublishing.org/oe/abstract.cfm?uri=oe-23-19-24557#Abstract

]]> 2019-05-13 08:22:25 UTC https://padlet.com/fl_keio/rbhwcruhm1tf/wish/359366544 Light interference pattern in a cobweb. https://padlet.com/fl_keio/rbhwcruhm1tf/wish/361516051 2019-05-19 17:32:03 UTC https://padlet.com/fl_keio/rbhwcruhm1tf/wish/361516051