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Pendulum Calculator
Enter the length — period and frequency update instantly.
Formula
T = 2π · √(L/g) | f = 1/T (g = 9.80665 m/s²)
Key facts
A 0.994 m pendulum has T = 2 s (the "seconds pendulum"). Period is independent of mass and almost independent of swing amplitude (small angles).
FAQ
Does a heavier bob swing slower?
No — mass cancels out of the equation. Only length and local gravity set the period.
When does the small-angle approximation break?
Beyond about 15–20° amplitude the real period runs slightly long; at 30° the error is ~1.7%.