(R+h)2GM=R3GM(R−h)
R3=(R+h)2(R−h)
=(R2+h2+2hR)(R−h)
R3=R3+h2R+2hR2−R2h−h3−2h2R
h3+h2(2R−R)−R2h=0
h3+h2R−R2h=0
h2+hR−R2=0
h=2−R±R2+4(1)R2
=2−R+5R
=2(5−1)R
The height ‘h’ at which the weight of a body will be the same as that at the same depth ‘h’ from the surface of the earth is (Radius of the earth is R and effect of the rotation of the earth is neglected)
Held on 2 Sept 2020 · Verified 6 Jul 2026.
25R−R
2R
25R−R
23R−R
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