# Power Thesaurus

How do you even find ‘pince-nez’, let alone pronounce it?
The answer: do a search for ‘eyeglasses’ in Power Thesaurus.
keywords: synonyms, pronunciation, eyeglasses

# rockets

A rocket is a device for trading mass for speed. The generic (i.e., gravitationally neutral) mathematical model of this is the equation p = qlog(m(i)/m(f)), where p is the increase in speed, q is the rate of loss of mass (that is, of mass ejection, assumed to be constant over the time interval in question), m(i) is the initial mass of the device (that is, of the rocket), and m(f) is the final mass of the device (that is, what mass remains after the mass to be ejected has been in fact ejected). This equation was published in 1903 by Konstantin Tsiolkovsky 23 years before Robert H. Goddard’s first liquid-fuel rocket was launched in 1926.
Notice how that fact that the logarithm of unity is zero neatly captures the fact that if no mass is ejected, then there is no increase in speed.
Here is the Wikipedia article on this equation.
keywords: Mathematics, Physics, ideal rocket equation, Tsiolkovsy rocket equation

# The Birthday Problem

There is a famous problem in Probability Theory that is phrased in terms of birthdays: What is the smallest number such that a randomly selected group of people of that number will have the same birthday (that is, month and day, ignoring the phenomenon of leap years)? People guessing the answer usually greatly over-shoot the mark. The number is surprisingly small: 23. This answer is so counter-intuitive that the ‘birthday problem’ is sometimes referred to as the ‘birthday paradox’.
Here is the Wikipedia article on this.

# warm-hearted vulgarity

“The keynote of American civilization is a sort of warm-hearted vulgarity.”
— Raymond Chandler
keywords: attitude, conduct, Psychology

# our destined end

Here’s the scoop.
keywords: poem, advice, Longfellow, A Psalm of Life