A body of weight 72 N moves from the surface of earth at a height half of the radius of earth, then gravitational force exerted on it will be

Question

A body of weight 72 N moves from the surface of earth at a height half of the radius of earth, then gravitational force exerted on it will be (A) 36 N (B) 32 N (C) 144 N (D) 50 N

Tardigrade Admin · Accepted Answer

F text surface =G (M m/Re2) FRe / 2=G (M m/(Re+Re / 2)2)=(4/9) × F text surface =(4/9) × 72=32 N .

Q. A body of weight $72 N$ moves from the surface of earth at a height half of the radius of earth, then gravitational force exerted on it will be

36 N

32 N

144 N

50 N

$F_{surface} = G \frac{M m}{R _{e}^{2}}$
$F_{R_{e} /2} = G \frac{M m}{( R _{e} + R _{e} /2 ) ^{2}} = \frac{4}{9} \times F_{surface}$
$= \frac{4}{9} \times 72 = 32 N .$

Q. A body of weight 72N moves from the surface of earth at a height half of the radius of earth, then gravitational force exerted on it will be