A bomb is dropped on an enemy post by an aeroplane flying. With a horizontal velocity of 60km/hr and at a height of 490 m. how far the aeroplane must be from the enemy post at the time of dropping the bomb, so that it may directly hit the target? `(g=9.8m//s^(2))`

Options

A. `(400)/(3)m`
B. `(500)/(3)m`
C. `(1700)/(3)m`
D. 498 m

Answer

B

Explanation

Let t be the time taken by the bomb to hit the target
`:. t = sqrt((2h)/g)=sqrt((2xx490)/(9.8))s=sqrt100s=10 s`
` x = " ut " = (60xx5/18)ms^(-1)xx 10 s=(500)/3 m`