Add new comment

Want facts and want them fast? Our Maths in a minute series explores key mathematical concepts in just a few words.
What do chocolate and mayonnaise have in common? It's maths! Find out how in this podcast featuring engineer Valerie Pinfield.
Is it possible to write unique music with the limited quantity of notes and chords available? We ask musician Oli Freke!
How can maths help to understand the Southern Ocean, a vital component of the Earth's climate system?
Was the mathematical modelling projecting the course of the pandemic too pessimistic, or were the projections justified? Matt Keeling tells our colleagues from SBIDER about the COVID models that fed into public policy.
PhD student Daniel Kreuter tells us about his work on the BloodCounts! project, which uses maths to make optimal use of the billions of blood tests performed every year around the globe.
Combining Yellow and Blue light does not give green light. It makes white light. Light is additive color mixing. 'Yellow and blue make green' only refers to paint. If i have paint that reflects yellow, in actuality it ABSORBS all other colors besides yellow (subtractive color mixing). So by mixing paints I DECREASE the spectrum of light that is reflected, and get green.
Adding waves isn't as simple as averaging the frequency. Mixing two waves with different frequencies actually gives a wave with two parts: one part that is the average frequency, like you said, and another part that is the difference between the frequencies, which creates "beating."
More here: http://www.acs.psu.edu/drussell/demos/superposition/superposition.html
So yes, the result is a wave that has a frequency similar to a 'B' when you hit those two notes at the same time, but it sounds different because of beating. Real music is also comprised of a bunch of different harmonics and beats, it's not just pure sine waves for each note. So you get a much more complex sound by hitting chords.