Answer:
Height will be 0.41 r
Explanation:
We have given acceleration due to gravity at any height is [tex]g_{new}=4.9m/sec^2[/tex]
Radius of the earth = r
We know that acceleration due to gravity at any height is given by
[tex]g'=\frac{GM}{(R+h)^2}[/tex]----eqn 1
And acceleration due to gravity at earth [tex]g=\frac{GM}{R^2}[/tex]----eqn2
Dividing eqn 2 by eqn 1
[tex]\frac{g}{g'}=\frac{(r+h)^2}{r^2}[/tex]
[tex]\frac{9.8}{4.9}=\frac{(r+h)^2}{r^2}[/tex]
[tex]2r^2=(r+h)^2[/tex]
[tex]\sqrt{2}r=h+r[/tex]
h = 0.41 r