Question

Question #0031c

Answer 1

Use the law of universal gravitaion.

Explanation:

This question is too vague to answer, but if you are refering to universal gravity between an object and the earth, use the law of universal gravitation.

`F=(GMm)/r^2` where
`F`: force,
`G`: gravitational constant(`G=6.67*10^-11 m^3kg^-1s^-2`),
`M`: mass of the earth,
`m`: mass of the object, and
`r`: distanse between the center of gravity of the object and that of the earth.

If an object is at the height `h=R` from the earth surface, substitute `r=2R` to the formula.
Since the universal gravity is proportional to `r^-2`, the force of gravity at `h=R" "(r=2R)` will be one-forth of the force at `h=0" "(r=R)`.