Question

A rock falls from rest a vertical distance of 0.72 meter to the surface of a planet in 0.63 second. What is the magnitude of the acceleration due to gravity on the planet?

Answer 1

S = 0.72 m,  t=0.63 s
s = a · t² /2
0.72 m = a · (0.63 s )² / 2       
a · 0.3969 s² = 1.44 m 
a = 1.44 m : 0.3969 s² = 3.628 m/s²
The magnitude of the acceleration due to gravity on the planet is 3.628 m/s²