Q. At a distance 320 km above the surface of earth, the value of acceleration due to gravity will be lower than its value on the surface of the earth by nearly (radius of earth = 6400 km)
A) 2%
B) 6%
C) 10%
D) 14%
Explanation
(c) $\frac{g'}{g} = 1 - \frac{2h}{R} = 1 - \frac{2 \times 320}{6400} = 1 - \frac{1}{10} = \frac{9}{10}\ $
$\therefore$ % decrease in $g = \left( \frac{g - g'}{g} \right) \times 100$
$= \frac{1}{100} \times 100 = 10\%$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.