A) 3.9m/s2
B) 9.65 m/s2
C) 7.75 m/s2
D) 5.25 m/s2
Correct Answer: B
Solution :
Key Idea: As we go below the surface of the earth the value of acceleration due to gravity goes on decreasing and becomes zero at the centre of the earth. Value of g at a depth h below the surface of earth is given by \[g'=g\left( 1-\frac{h}{{{R}_{e}}} \right)\] where \[{{R}_{e}}\] is radius of earth. Given, \[h=100\,km={{10}^{5}}m\] \[{{R}_{e}}=6400\,km=64\times {{10}^{5}}m\] \[\therefore \] \[g'=g\left( 1-\frac{h}{{{R}_{e}}} \right)\] \[=9.8\left( 1-\frac{{{10}^{5}}}{64\times {{10}^{5}}} \right)\] \[=9.8\left( 1-\frac{1}{64} \right)=9.65\,m/{{s}^{2}}\]You need to login to perform this action.
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