Gravitation Question 132
Question: A body is projected vertically upwards from the surface of a planet of radius R with a velocity equal to half the escape velocity for that planet. The maximum height attained by the body is [KCET (Engg./Med.) 2002]
Options:
A) R/3
B) R/2
C) R/4
D) R/5
Show Answer
Answer:
Correct Answer: A
Solution:
If body is projected with velocity v $ [(v<v_{e})] $ then height up to which it will rise, $ [h=\frac{R}{\frac{v_{e}^{2}}{v^{2}}-1}] $ $ [v=\frac{v_{e}}{2}] $ (given) \ $ [h=\frac{R}{{{\left( \frac{v_{e}}{v_{e}/2} \right)}^{2}}-1}=\frac{R}{4-1}=\frac{R}{3}] $