An object is thrown vertically from a height of #15 m# at # 6 m/s#. How long will it take for the object to hit the ground?
Velocity of object when it hits the ground is
Total time taken
The time is about 2.5 s.
Compared to your first answer, this is an alternate method of solving.
I will choose to have up be the positive direction. Use the kinematic (suvat) formula
#s = -15 m#because it will hit the ground - below the point it was thrown from #u = 6 m/s#positive because it was thrown up #a = -g = -9.8 m/s^2#.
Now, plugging in the data and solving for t
Adjust so that all 3 are on one side and zero is on the other (preparing for use of the quadratic equation)
The - part of the
I hope this helps,