Discussion Forum



1)

The value of gravititational acceleration g at a height h above the earth's surface is $\frac{g}{4}$ , then (R=radius of earth)


A) h=R

B) $h=\frac{R}{2}$

C) $h=\frac{R}{3}$

D) $h=\frac{R}{4}$

Answer:

Option A

Explanation:

 The value of acceleration due to gravity g at a height h is given by

 $g'= g\left( \frac{R_{e}}{R_{e}+h}\right)^{2}$

[ Symbols have their usual meanings]

when,

 g'= $\frac{g}{4}$   and $R_{e}$= R

 So, $\frac{g}{4}= g\left( \frac{R_{}}{R_{}+h}\right)^{2}$

 $\frac{1}{2}= \frac{R_{}}{R_{}+h}$

 $\Rightarrow$     2R= R+h

  $\Rightarrow$     R= h