Calculating the Force of Gravity on a 1-kg Mass at Twice Earth's Radius

[vitaly]

Calculate the force of gravity on a 1-kg mass if it were 6.4 x 10^6 m above Earth's surface (twice Earth's radius).

Known: Mass of object 1 = 1 kg
Mass of Earth = 6 x 10^24 kg
Earth's radius = 6.4 x 10^6 m; 2x this is 1.28 x 10^7 m
G = 6.67 x 10^-11 N*m^2/kg^2

Equation: F = G(Mass of object)(Mass of Earth)/(Distance)^2
= (6.67 x 10^-11 N*m^2/kg^2)(1 kg)(6 x 10^24 kg)/(1.28 x10 ^7 m)^2
= 2.4 N

 

[stunner5000pt]

yes you did it right

it's simply asking you for hte attraction force between the object and earth, really.

 

[vitaly]

Ok, thank you for checking.