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Dimensional analysis is a powerful instrument in the physicist's arsenal, It not only helps to check equations, but can also be used to derive important ones. We illustrate this by deriving some important expressions in black hole physics. Starting with a simple input, namely that the properties of an uncharged, non-rotating black hole depend only on the mass (that 'no hair theorem') we employ dimensional analysis to derive expressions for the area of the event horizon, the entropy, the evaporation time and the Hawking temperature, among others. Our derivations are accessible to pre-college students, but its exotic implications may leave them pondering for a very long time. [ABSTRACT FROM AUTHOR]

The article presents several examples of Fermi problems adapted from the 37th International Physics Olympiad (IPO) held in Singapore from July 8-17, 2006. The two effects that were used to determine the camera's effectiveness as a photographic tool are diffraction by the aperture and the pixel size. It cites the amount of cooking time needed to make a hard-boiled egg. The solution to know the frames in an animation movie is presented.