dhruba
Last Activity: 3 Years ago
listing the facts …
set the point from where the ball was thrown as origin and follow sign convention
initial velocity of the ball(u)= +8 m/s(not -8m/s)
height to be covered(s)=-3m
acceleration is only due to gravity(g)_=-10 m/s^2
using equation we get -3=8(t)+1/2 (-10)(t^2) solving u get t=3/5 sec or 1 sec