Assuming the earth to be a sphere of uniform mass density, how much would a body weigh half way down to the centre of the earth if it weighd 250 N on the surface ?

Explanation

W = mg = 250 N
Therefore, `m = (250)/(9.8) kg`
As `d = (R )/(2)`
`g_(d) = (1-(d)/(R ))g`
`g_(d) = (1-(1)/(2)) xx 9.8`
`g_(d) = 4.9 ms^(-2)`
Weight of the body `= mg_(d) = (250)/(9.8) xx 4.9 = 125 N`.