A target plane flies at 2100 meters. An antiaircraft gun fires a projectile with an initial upward velocity of 200 m/sec. Will the projectile ever reach the altitude of the target plane?

1 Answer

NO, because Maximum height is only
s=2,040.82" "meters

Explanation:

From the given : height of the plane=2100 meters

From Physics, s=v_o *t+1/2*g*t^2 and v_o=200" "m/sec
The g=-9.8 " "m/sec^2(negative because accelaration due to gravity is directed downward)

s=v_o *t+1/2*g*t^2

s=200*t+1/2*-9.8*t^2

To determine the maximum, we convert this parabolic equation to its Vertex Form by completing the square

s=-9.8/2*t^2+200t

s=-9.8/2(t^2-400/9.8*t)

s=-9.8/2(t^2-400/9.8*t+(200/9.8)^2-(200/9.8)^2)

s=-9.8/2(t-200/9.8)^2+9.8/2*(200/9.8)^2

simplify first

s=-9.8/2(t-200/9.8)^2+20000/9.8
s-20000/9.8=-9.8/2(t-200/9.8)^2

(t-200/9.8)^2=-2/9.8(s-20000/9.8)

This is the vertex form (x-h)^2=-4p(y-k)

Maximum s=20000/9.8=2040.82" "meters

This is not enough to hit the plane at 2100 meters

God bless.... I hope the explanation is useful.