Academic Integrity: tutoring, explanations, and feedback — we don’t complete graded work or submit on a student’s behalf.

The radius of the Earth is about 6400 km. An astronaut, who weighs 800 N when su

ID: 582194 • Letter: T

Question

The radius of the Earth is about 6400 km. An astronaut, who weighs 800 N when surface of the earth, is floating inside a space station orbiting the Earth at an altitude of 400 km above its surface. What is the magnitude of the gravitational force of the Earth on the astronaut? 0 N 800 N Times (400 / 6800)^2 (this is much less than 800 N) 800 N Times (400 / 6400)^2 (this is also much less than 800 N. but greater than the value of (B)) 800 N Times (6400 / 6800)^2 (this is only slightly less than 800 N) 800 N Some other planet (Planet Q) has half the mass of the Earth and its diameter is half the Earth's diameter. How does the acceleration of gravity on the mu face of Planet Q. gQ, compare to the acceleration of gravity on the surface of the Earth, g?

Explanation / Answer

New acceleration due to gravity would be

g' = GM/(R+h)^2, R = 6400, h = 400

so, B is CORRECT

2)

Relation is g = GM/R^2

Now Mass is halved and Radius is halved

so, g becomes Twice the existing g

so, g0 = 2*g

D is correct