How would one calculate the force of gravity on the 1.4-kg mass if it were 1.9 x10 ^ 7 m above the earth 's surface -LRB- that is it were four earth radii from earth 's center -RRB- ?
Jupiter 's mass is about 300 times than that of Earth , yet surface gravity on Jupiter is only about 2.5 times that of Earth 's . What 's the best explanation ?