Question

Calculate the force of gravity on the 0.50-kg mass if it were 6.4×106 m above earth's surface (that is, if it were two earth radii from earth's center).

Answer 1

Radius of Earth is given as

`R = 6.4 * 10^6 m`

now here the height from the surface of earth is same as that of radius

`h = 6.4 * 10^6 m`

now here the acceleration due to gravity at this height is given as

`g' = (GM)/((R+h)^2)`

`g' = (GM)/(4R^2)`

`g' = (g)/(4)`

now the force of gravity on the given object will be

`F = mg'`

`F = m*(g)/(4)`

`F = 0.5 * (9.8)/(4)`

`F = 1.225 N`

so the force of gravity on it is 1.225 N