Question

1. While strolling along on unknown planet, an astronaut decides to throw a hammer and a feather upwards at 5.0 m/s. They both return to the point of release in 3.0 s. What is the acceleration due to gravity on Planet X.
2. Marii jumps straight upward at 15.0 m/s. How high is he when he is traveling at 8.0 m/s upwards ?

Please help me ! Thank you !!!

Answer 1

reaches top in 1.5 seconds
v = Vi - g t
0 = 5 - 1.5 g
g = 5/1.5 = 3.33 m/s^2

v = 15 - 3.33 t
8 = 15 - 3.33 t
t = 2.1 seconds
h = 15 t - (3.33/2) t^2