A drone is ascending vertically at a constant speed of 5 m s ⁻¹ . When it is at a certain height above the ground, a small package gets detached from it. If the package takes 6 s to strike the ground, what was the height of the drone at the instant the package was detached? (Take g = 10 m s ⁻² )

Step-by-step solution

When the package is detached from the drone, it acquires the initial velocity of the drone. Initial velocity of the package, u = 5 m s ⁻¹ (upwards) Time taken to reach the ground, t = 6 s Acceleration due to gravity, a = -10 m s ⁻² Let the height of the drone at the instant of detachment be h . The displacement of the package when it strikes the ground is s = -h . Using the second equation of motion, s = ut + 1 2 at^2 : -h = 5 6 + 1 2 (-10)(6)^2 -h = 30 - 5 36 -h = 30 - 180 -h = -150 h = 150 m Answer: 150 m