The height of any point P above the surface of earth is equal to diameter of earth. The value of acceleration due to gravity at point P will be (Given g = acceleration due to gravity at the surface of earth).
- \(\frac g2\)
- \(\frac g4\)
- \(\frac g3\)
- \(\frac g9\)
The Correct Option is D
Solution and Explanation
We know that
\(g' = \frac {GM}{(R+h)^2}\)
Given \(h = 2R\)
\(g' = \frac {GM}{(R+2R)^2}\)
\(g' = \frac {GM}{(3R)^2}\)
\(g' = \frac {GM}{9R^2}\)
\(g' = \frac {g}{9}\)
so, the correct option is (D): \(\frac g9\)
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Concepts Used:
Acceleration
In the real world, everything is always in motion. Objects move at a variable or a constant speed. When someone steps on the accelerator or applies brakes on a car, the speed of the car increases or decreases and the direction of the car changes. In physics, these changes in velocity or directional magnitude of a moving object are represented by acceleration.
