› added 8 years ago

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TIL rubbing (or isopropyl) alcohol usually comes in three concentrations: 70%, 91%, and 99%. The 70% dissapates slower and should not be used to clean electronics.

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91vQ TIL that glass is transparent because of quantum mechanics, not due to the density of the particles. Basically since there are discrete energy states, if the photon can’t excite the electron up to the next orbital, it just falls back down and shoots the photon out with the same momentum as before.
J1YDj TIL that Montana Pool Service is a non-profit organization founded by Jeff Ament of Pearl Jam, that builds skateboard parks in rural and native communities in Montana. So far its funded over 20 parks.
GdBJ TIL the optimal strategy of finding a good partner is to reject the first 37% of potentials, and then pick the first person better than anyone seen so far
xp61 TIL: Safety Beach located in Victoria, Australia. Changed its name from Sharks Cove to Safety Beach, to encourage more tourists to visit
VMPk0 TIL that airport runways at higher elevations need to be longer because the thin air at high elevations results in less lift on the aircraft