Time taken by the packet

shehri

1. The problem statement, all variables and given/known data

A Helicopter is vertically moving upward with speed of 8m/s.At a height of 122.8m from ground,a packet is fallen from the Heli window.How much time would the packet take for hitting to ground?

2. Relevant equations

vf=vi+gt.
S=vit+1/2gt^2
2aS=vf^2-vi^2

3. The attempt at a solution

chanvincent

You have the initial speed of the packet, also the distance from the ground, and you are required to find t,
Which of the three equations you gonna use?
a.) vf=vi+gt.
b.) S=vit+1/2gt^2
c.) 2aS=vf^2-vi^2

cristo

Well... what have you tried? Show your work please.