Equations · equation
Pendulum Period
Mechanics · 1673
- Equation
- T = 2π √(L/g) (small swings)
- Field
- Mechanics
- Symbols
- T the period of one full swing · L the length from pivot to centre of mass · g the local gravitational acceleration
- Year
- 1673
Significance
The period depends on the length and on gravity — not on the mass, and, for small swings, not on the amplitude. Galileo noticed the last in 1602; Huygens made a clock of it in 1657 and derived the formula in 1673. It is the small-angle approximation applied to SHM, and it made g measurable to four figures with a string and a stone.
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