Question

Hey mate !Can you please answer this question

ITS URGENT...........

A balloon is rising upward with a constant speed 10 m/s when It is at 75 m height from ground then a stone is dropped from it. Find the time taken by stone to reach the ground.. ​

Answer 1

At the time of dropping the stone, let the height of balloon (and stone) be H. Let that be t = 0 sec.

At t = 0 sec, the stone is also traveling with a speed of 16 m/s upwards.

The additional height it reaches = h. Let g = 10 m/s²

  v² = u² - 2 g h    =>   h = 16²/(2*10) = 12.8 m

Time taken to reach the maximum height = t1

    v = u - g t   =>   t1 = 16/10 = 1.6 sec 

Time taken to fall the height of  H + 12.8 m = t2 = 4 s - 1.6s = 2.4 s

So    s = u t + 1/2 g t²   =>    H + 12.8 = 0 + 1/2 * 10 * 2.4²

          H = 28.8 - 12.8 = 16.0 m

Apply this question.......On that it will help u..

Answer 2

the answer depends soon the mass of the stone

I guess 2.4 seconds