# Pendulum mechanics

Michael Lorrey (retroman@tpk.net)
Thu, 17 Jul 1997 20:13:40 -0400

I thought I'd post this question for those even more scientifically
abled than I to explain:

How can a little kid (or an adult for that matter) sit on a perfectly
still playground swing, begin rocking back and forth, and within a
minute be wizzing back and forth to a pretty good height, without ever
touching the ground or other still grounded object?

Anyone who can supply their own answers, with equations if possible, is

```--
TANSTAAFL!!!
Michael Lorrey
------------------------------------------------------------
mailto:retroman@tpk.net		Inventor of the Lorrey Drive
Agent Lorrey@ThePentagon.com
Silo_1013@ThePentagon.com	http://www.tpk.net/~retroman/

Mikey's Animatronic Factory
My Own Nuclear Espionage Agency (MONEA)
MIKEYMAS(tm): The New Internet Holiday
Transhumans of New Hampshire (>HNH)
------------------------------------------------------------
#!/usr/local/bin/perl-0777---export-a-crypto-system-sig-RC4-3-lines-PERL
@k=unpack('C*',pack('H*',shift));for(@t=@s=0..255){\$y=(\$k[\$_%@k]+\$s[\$x=\$_
]+\$y)%256;&S}\$x=\$y=0;for(unpack('C*',<>)){\$x++;\$y=(\$s[\$x%=256]+\$y)%256;
&S;print pack(C,\$_^=\$s[(\$s[\$x]+\$s[\$y])%256])}sub S{@s[\$x,\$y]=@s[\$y,\$x]}
```