question_answer

At what height from the surface of earth the gravitation potential and the value of g are \[\,\,5.4\times {{10}^{7}}\text{ }J\text{ }k{{g}^{2}}\] and \[6.0\text{ }m{{s}^{-2}}\] respectively?

Take the radius of earth as 6400 km: [NEET - 2016]

A) 2600 km

B) 1600 km

C) 1400 km

D) 2000 km

Correct Answer: A

Solution :

[a]           (1)

And                   (2)

dividing (1) and (2)

so