Question

An astronaut is standing on the surface of a planetary satellite with no atmosphere that has a radius of 1.74 × 106 m and a mass of 7.35 × 1022 kg. An experiment is planned where a projectile needs to be launched straight up from the surface. What must be the minimum initial speed of the projectile, so it will reach a height of 2.55 × 106 m above this satellite’s surface? (G = 6.67 × 10-11 N ∙ m2/kg2)

Answer 1

First finding the acceleration due to gravity of the planet,

Radius of planet,

Mass of planet,  

Universal gravitational constant,

Substituting :

Using third equation of motion, Speed,

Maximum Height,

Substituting :