This is the first in our weekly look at the world’s greatest physics sitcom, The Big Bang Theory. (It’s the greatest ’cause it’s the first.)
In last night’s episode of the Big Bang Theory, Penny and Wolowitz decide to throw a surprise birthday party for Leonard. Assigned the task of keeping Leonard out of his apartment until the party, Wolowitz willingly bites into a peanut buttery piece of food, knowing that he will have a severe allergic reaction and Leonard will have to stay with him at the Hospital. The perfect diversion.
Amid the craziness, The Feynman Lectures on Physics were mentioned, a copy of which Leonard receives as a birthday present from Wolowitz. The Feynman Lectures on Physics, by Richard Feynman, Robert Leighton, and Matthew Sands is considered a classic introduction to modern physics. Printed in a dozen languages, with more than 1.5 million copies sold in English alone, it is one of the most popular books on physics ever written.
Less technical that Feynman’s other works, the book is divided into three volumes, the first of which contains lectures on mechanics, radiation and heat. The second volume focuses on electromagnetism and matter, and the third volume explains quantum mechanics.
Reminiscing over his history of terrible birthdays, Wolowitz remembers wanting a titanium centrifuge to separate radioactive isotopes for his 12th birthday (he got a dirt bike instead…). Every chemical element (whether it’s magnesium, oxygen, or anything else) occurs in nature with slightly different masses, called isotopes. Radioactive isotopes spontaneously break apart. Separating isotopes isn’t too difficult if you’ve got a machine that creates centrifugal forces by spinning at high speeds. Centrifugal forces can be used to separate particles with different densities.
As the centrifuge rotates in a circular motion, the paths of particles with different densities are affected by the centrifugal force being generated. Separation occurs because less dense particles usually travel near the center of the circular path, while denser particles, which travel in a straighter path, tend to be found outside of the circular path.