Physics
Mechanics
Easy
Question
Assuming earth to be a sphere of a uniform density, what is the value of gravitational acceleration in a mine 100 km below the earth's surface (Given R=6400 km)
The correct answer is:
Acceleration due to gravity at depth 
=g\left[1-\frac{100}{6400}\right]=9.8\left[1-\frac{1}{64}\right]=9.8 \times \frac{63}{64}=9.66 m / s ^{2}
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