Answer:
Step-by-step explanation:
First we have to find out the gravity on that planet. We use Newton second equation of motion. It is given as,
![s = ut + (1)/(2) gt^(2)](https://img.qammunity.org/2021/formulas/physics/high-school/3ytp0frgcx3ix29xadgfj6ncubyu7xg3ko.png)
Distance s = 18 m
Time t = 2.5 s
Velocity u = 0
By putting these values,
18 = 1/2.g.(2.5)²
g = 5.76
So the gravity on that planet is 5.76. Lets find out the weight of the astronaut.
Mass of the astronaut on earth m = 68.5 kg
Weight of astronaut on earth W = mg = (68.5)(9.8) = 671.3 N
Weight of astronaut on earth like planet = (68.5)(5.76) = 394.56 N
x = 394.56 N