As astronaut on a strange planet can jump a miximum hirizontal distance of 15m if his initial speed is 3m/s what is the free fall acceleration on the planet

Answer 1

Assume you know max is when takeoff angle is 45 deg above horizontal
horizontal component = u = speed s * cos 45 = 3 cos 45 = 2.12 m/s
t = 15/u = 15/2.12 = 7.07 seconds, wow, not much g
now vertical problem
stops at top when v = 0 at 7.07/2 = 3.54 seconds
v = Vi - g t
0 = 2.12 - g (3.54)
g = 0.6 m/s^2
this is a planet? Not an asteroid ?