Answer:
1.40625m/s²
Step-by-step explanation:
Using the equation of motion expressed as v = u+gt where;
v is the final velocity of the ball
u is the initial velocity
g is the acceleration due to gravity
t is the time taken
Given
u = 9m/s
v = 0m/s
t = 6.4s
Required
acceleration due to gravity g
Since the rock is thrown up, g will be a negative value.
v = u+(-g)t
0 = 9-6.4g
-9 = -6.4g
6.4g = 9
divide both sides by 6.4
6.4g/6.4 = 9/6.4
g = 1.40625m/s²
Hence the acceleration due to gravity on the planet is 1.40625m/s²