The blue LED was supposed to be impossible—until a young engineer proposed a moonshot idea. Head to https://brilliant.org/veritasium to start your free 30-da...
The blue LED was supposed to be impossible—until a young engineer proposed a moonshot idea.
Doppler effect?
https://en.m.wikipedia.org/wiki/Redshift#Blueshift
Essentially yes
Yeah but it only works if the source is moving towards the observer