Acceleration due to gravity on the surface of moon, g = 1.7 m s–2
Acceleration due to gravity on the surface of earth, g = 9.8 m s–2
Time period of a simple pendulum on earth, T = 3.5 s
T = 2π √l/g
Where, l is the length of the pendulum
Hence, the time period of the simple pendulum on the surface of moon is 8.4 s.