By Casey Lynn
Contributing Writer, [GAS]

As if we don’t see enough equations in physics textbooks, sometimes they sneak up on us when we’re least expecting them.

Some of the equations pictured are “famous” (though some are definitely not); please feel free to boast your equation-spotting skills in the comments. It’s like bird watching. “Oh look, there’s Maxwell’s! There’s gravitational momentum!” Of course, clicking through to the flickr page first is cheating. Those of you fond of geeky tattoos might like some of these as well. So get out your pens and paper and… begin.

problem #1 (barredo – CC), problem #2 (julishannon – CC), problem #3 (urban_data – CC), problem #4 (ztephen – CC), problem #5 (reallyboring – CC), problem #6 (mmechtley – CC), problem #7 (dfisher81 – CC), problem #8 (breakingglass – CC), problem #9 (yufengzi – CC), problem #10 (edyson – CC), problem #11 (antoniapneumonia – CC), problem #12 (xnxbox – CC)