Answer:
314.92 m
Explanation:
Acceleration of the helicopter = 5.4 m/s² = a
Time taken by the helicopter to reach maximum height = 10.8 s = t
Initial velocity = 0 = u
Final velocity = v
Displacement = s
Equation of motion
[tex]s=ut+\frac{1}{2}at^2\\\Rightarrow s=0\times 10.8+\frac{1}{2}5.4\times 10.8^2\\\Rightarrow s=314.92\ m[/tex]
Maximum height above ground reached by the helicopter is 314.92 m