Q. A balloon is moving up with a speed 60 m/s.When the balloon is at a height 225 m above the ground a stone is thrown horizontally with a speed 40 m/s with respect to balloon.
a) The horizontal displacement of the stone when it is at the top of its trajectory.
At the moment of throwing, the stone will possess two components of velocity,
1. Upward, 60m/s
2. Horizontal, 40 m/s
At the top of its trajectory, the vertical component of velocity is zero. Applying laws of motion for this component,
t = 60/g =60/9.81=6.1155 s
This is the time to reach the top of its trajectory.
a) Horizontal range covered by the stone in this time = horizontal velocity * time
Therefore, the horizontal displacement of the stone when it is at the top of its trajectory is 244.6 m.