IF you take a charged parallel plate capacitor and increase the distance between its plates, you will find that you have to have to do work to overcome the attractive Coulomb force between the plates. If the capacitor plates have area A, and a surface charge density sigma, the amount of work you have to do to increase the plate separation by an amount delta d is...

If you look at table salt (NaCl) being heated by a Bunsen burner flame, you will see a very bright yellow color in the resulting flame. This yellow is a characteristic footprint of the element sodium, Na, of which salt, NaCl, is comprised. The more general technique of looking at the spectrum of light emitted (and absorbed) by a substance to identify its constituent atoms...

One of the truly great physicsist of the 20th century, Bethe did fundamental work in most major branches of physics, including atomic, nuclear, solid state, high energy and astrophysics. One might expect that his...

As a Polish student in Paris in 1892, Manya Sklodovska survived on a mere 40 Rubles a month. This translated into 3 francs per day -- which she subsisted on for three years. Not an easy existence considering her expenses included room and board (in a garret), clothes, books and...