Answer:
Magnitude of the acceleration due to gravity on the planet = 2.34 m/s²
Step-by-step explanation:
Time period of simple pendulum is given by
, l is the length of pendulum, g is acceleration due to gravity value.
We can solve acceleration due to gravity as

Here
Length of pendulum = 1.20 m
Pendulum executes simple harmonic motion and makes 100 complete oscillations in 450 s.
Period,

Substituting

Magnitude of the acceleration due to gravity on the planet = 2.34 m/s²