A projectile is thrown with an initial velocity `(ahati+bhati)m s^(-1)`.where `hati` and `hatj` are the unit vectors along horizontal and vertical directions respectively If the range of projectile is twice the maximum height reached by it, then

Options

A. a=2b
B. b=a
C. b=2a
D. b=4a

Answer

C

Explanation

`vecv=ahati+6hatjrArru cos theta=a` and `usin theta=b`
`tantheta=(b)/(a)` also `tan theta=(4)/(n)=(4)/(2)=2`
`therefore (b)/(a)=2 rArr b=2a`