Find the length of the pendulum if the oscillation period is 0.5 sec.

Problem data: T (oscillation period of the selected mathematical pendulum) = 0.5 s.

Reference values: g (acceleration due to gravity) = 9.81 m / s2.

Let us express the length of the selected mathematical pendulum from the following formula: T = 2 * Π * √ (l / g), whence √ (l / g) = T / (2 * Π); l / g = T ^ 2 / (4 * Π ^ 2) and l = T2 * g / (4 * Π ^ 2).

Let’s make a calculation: l = 0.5 ^ 2 * 9.81 / (4 * 3.14 ^ 2) = 0.0622 m or 6.22 cm.

Answer: The length of the chosen mathematical pendulum is 6.22 cm.