A shell is fired at a speed of $200\ m/s$ at an angle of $37^o$ above horizontal from top of a tower $80\ m$ high. At the same instant another shell was fired from a jeep travelling away from the tower at a speed of $10\ m/s$ as shown. The velocity of this shell relative to jeep is $250\ m/s$ at an angle of $53^o$ with horizontal. Find the time (in $sec$) taken by the two shells to come closest.
A shell is fired at a speed of $200\ m/s$ at an angle of $37^o$ above horizontal from top of a tower $80\ m$ high. At the same instant another shell was fired from a jeep travelling away from the tower at a speed of $10\ m/s$ as shown. The velocity of this shell relative to jeep is $250\ m/s$ at an angle of $53^o$ with horizontal. Find the time (in $sec$) taken by the two shells to come closest.
- A
$1$
- B
$2$
- C
$3$
- D
$4$
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