An object of unknown mass is initially at rest and dropped from a height h. it reaches the ground with a velocity of v1. ? the same object is then thrown down with 2v1 from the height h. how does the v final at the ground this time compare to v1?

Ahot-air balloon takes off from the ground traveling vertically with a constant upward acceleration of magnitude g/4. after time interval δt, a crew member releases a ballast sandbag from the basket attached to the balloon. how many seconds does it take the sandbag to reach the ground? (express your answer in terms of δt)