Calculating a pendulum's period
What is the period of a simple pendulum 2.5 m long, where g = 10 m/s²?
Answer C: explanation for every choice
A
This is √(L/g) without the 2π.
B
This uses π instead of 2π.
C
Correct. T = 2π√(L/g) = 2π√0.25 = 2π(0.5) ≈ 3.1 s.
D
This inverts L/g inside the square root.
TakeawayT = 2π√(L/g).
Equation usedPendulum period
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