Pendulum Formulas
Pendulums:

Florida gravity (30° latitude) = 32.1302

4Pi² / 32.1302 = 1.2287

1 / 1.2287 = .8138

A 2second period (ticktock) pendulum in Florida has a length of 39.065" (3.255').

These formulas actually apply to a pendulum with an infinitely small swing, but they give a reasonable approximation if the angle isn't too large!

Find Period when given Length
Time = SQRT ((4Pi² * Feet) / Gravity)
Time = SQRT (Feet * 1.2287)
Time = SQRT (Feet / .8138)
2 seconds = SQRT (3.255 * 1.2287)
2 seconds = SQRT (3.255 / .8138)

Find Length when given Period
Length (feet) = Time² * (Gravity/4Pi²)
Length (feet) = Time² * .8138
3.255 feet = 2² * .8138
