What is the acceleration of gravity on the planet if a meter-long pendulum makes 30 oscillations in 1.5 minutes?

Initial data: l (length of the pendulum) = 1 m; t (duration of oscillations of a meter pendulum) = 1.5 min; N (the number of oscillations that a meter-long pendulum made) = 30 oscillations.

SI system: t = 1.5 min = 90 s.

1) The period of oscillation of a meter pendulum: T = t / N = 90/30 = 3 s.

2) Acceleration of gravity on the planet: T = 2Π * √ (l / g), whence g = 4 * Π ^ 2 * l / T2 = 4 * 3.14 ^ 2 * 1/32 = 4.382 m / s2.

Answer: The acceleration of gravity on the planet is 4.382 m / s2.