Answer: 7.68 m/s²
Explanation: The period of a simple pendulum is given by the formula:
T = 2π√(L/g)
where T is the period, L is the length of the pendulum, and g is the gravitational acceleration.
In this problem, the pendulum completes 110 full swing cycles in a time of 133 s, which means that the period of the pendulum is:
T = 133 s / 110 = 1.209 s
Substituting this into the formula above and solving for g, we get:
g = (4π²L) / T² = (4π²)(0.51 m) / (1.209 s)² ≈ 7.68 m/s²
Therefore, the magnitude of the gravitational acceleration on this planet is approximately 7.68 m/s².