A fighter plane enters inside the enemy territory, at time `t=0`, with velocity `upsilon_(o)=250m//s` a moves horizontally with constant acceleration `a=20m//s^(2)` (see figure) An enemy tank at the border, spot the plane and fire shots at an angle `theta=60^(2)` with the horizontal and with velocity `u=600 m//s`.At what altitude `H` of the plane it can be hit by the shot?

Options

A. `1500 m`
B. `2473 m`
C. `1650 m`
D. `1800 m`

Answer

B

Explanation

If it is being hit then `d=v_(0)t+1/2at^(2)=(u cos theta)t`
or `t=(ucos theta-v_(0))/(a//2)`
`:. T=5s`
`H=(u sin theta)t-1/2 "gt"^(2)`
`H=1500sqrt3-125`
`rArr H=2473m`