A space projectile motion question (1 Viewer)

[x.Exhaust.x]

I can't seem to get my head around this simple question (which formulae should I use for both questions?)...

1. A plane drops emergency food rations to the Red Cross. The plane is travelling at 231km/hr and maintains a cnstant altitude above the flat land below. The ration drop takes 20.0 seconds, from when the food crate leaves the plane to the time it hits the ground.

a) Calculate the final vertical velocity of the food rations just before impact.

b) Calculate the plane's altitude.

 

[shady145]

a) use v=u + at
v=0+9.8x20
v=196m/s

b) use (delta)y=ut + .5at^2
(delta)y=0(20) + .5x9.8x20^2
(delta)y=4.9x400
(delta)y=1960 metres high

 

[x.Exhaust.x]

Thanks shady!