An object is thrown vertically from a height of #3 m# at #3 m/s#. How long will it take for the object to hit the ground?

1 Answer
Feb 19, 2016

Answer:

time = 1.6 sec

Explanation:

The object is thrown from a height 8m, when it reaches at ground its displacement h= - 8m, its initial upward velocity u = 3m/s
if acceleration due to gravity g is taken as -10 #ms^_2# then equation can be written as follows

#h =ut+1/2.g*t^2#
Or. -8 = 3t -0.5x10x#t^2#
Or #5t^2-3t-8 =0#
Or #(5t-8)(t+1) =0#
so feasible solution is t = 8/5 = 1.6 s