VITEEE 2009 Paper

Here, maximum height attained by a projectile
h=

v2R

2‌gR−v2

...(i)

Velocity of body = half the escape velocity
i.e., ‌v=

ve

2

or ‌‌‌v=

√2‌gR

2

⇒ ‌‌‌v2=

2‌gR

4

⇒ ‌‌‌v2=[

gR

2

]
Now, putting value of v2 in Eq.(i), we get
Height, ‌‌h=

gR 2 .R

2gR− gR 2

=

gR2 2

3‌gR 2

=

R

3