Question
Q IF A BODY IS PROJECTED UPWARD WITH SPEED 1/2 OF ESCAPE SPEED OF EARTH THEN MAXn HEIGHT ATTAINED BY IT IS=?
ANS=R/3 WHERE R=RADIUS OF EARTH
Joshi sir comment
escape velocity = √(2GM/R) so 1/2 of escape = 1/2√(2GM/R)
so according to given condition on applying energy conservation we will get
energy at start = energy at the heighest point
or -GMm/R + mv2/2 = -GMm/R1 + 0
or - GMm/R + 2GMm/8R = -GMm/R1 + 0
solve now for finding R1 then find R1-R
Read 1 Solution.
use energy conservation
-GMm/R +2GMm/8R = 0+ -GMm/R1 where R1 is the distance from the centre of the earth.
solving it u wll get R1 = 4R/3 so h= 4R/3-R =R/3 Ans.
Best SolutionNIKHIL VARSHNEY 12 year ago
is this solution helpfull: 1 0