question_answer

The value of acceleration due to gravity at Earth's surface is\[9.8\text{ }m{{s}^{-2}}\]. The altitude (in metre) above its surface at which the acceleration due to gravity decreases to \[4.9\text{ }m{{s}^{-2}},\] is close to : (Radius of earth \[=6.4\times {{10}^{6}}m\])

Answer:

\[\left( \mathbf{2}.\mathbf{6}\times \mathbf{1}{{\mathbf{0}}^{\mathbf{6}}} \right)\]