Which of the following statements are true about acceleration due to gravity?

Options

A. 'g' decreases in moving away from the centre of earth if `r gt R`
B. g' decreases in moving away from the centre of earth if `r lt R`
C. g' is zero at the centre of earth
D. g' decreases if earth stops rotating on its axis

Answer

AC

Explanation

Variation of g with distance : If `r gt R` then `g prop 1/r^(2)" ":.` (A) is correct
If `r lt R` then `g prop r" ":.` (B) is incorrect & (C) is correct
variation of g with `omega : g'=g-omega^(2) R cos^(2) lambda`
If `omega=0` then g will not change at poles where `cos lambda =0`. while at other point g increases
`:.` (D) is incorrect.