A body weights 500 Non the surface of earth. At what distance below the surface of earth it weight $250 \mathrm{~N}$ ? (Radius of earth, $R=6400 \mathrm{~km}$ )

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Aicharya · Accepted Answer

Value of acceleration due to gravity decreases on going below the surface of the earth. Weight $(w)$ of a body is defined as product of mass $(m)$ and acceleration due to gravity $w=m g$. The value of g below the surface of earth at a distance $h$ is given by, $\begin{aligned} & g^{\prime}=g\left(1-\frac{h}{R}ight) \ & \Rightarrow W^{\prime}=W\left(1-\frac{h}{R}ight)\end{aligned}$ Given, $W^{\prime}=250 \mathrm{~N}$ and $W=500$ $\begin{aligned} & 250=500\left(1-\frac{h}{R}ight) \ & \Rightarrow h=\frac{R}{2}=32000 \mathrm{~km}\end{aligned}$ ~

A body weights 500 Non the surface of earth. At what distance below the surface of earth it weight $250…

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