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hulk
Nov14-04, 02:46 PM
A 1550 kg weather rocket accelerates upward at 10m/s^2. It explodes 2 s later after liftoff and breaks into two fragments, one twice as massive as the other. Photos reveal that the lighter fragment traveled straight up and reached a maximum height of 530m.
What was the speed of the heavier fragment just after the explosion.

The way Im approaching is this
Since momentum is conservedd

mv = m1v1 + m2v2
m1 = 500 kg smaller piece
m2 = 1000kg larger piece

I find v
v = at = 20m/s

Iam confused as to how to find v1.
I know only distance gone upward 530m
Should I apply
Vfinal^2 - Vinitial^2 = 2ax where Vfinal is 0 and a is 9.8
This Vfinal is speed of smaller fragment
Once I find this I can find v2 by putting it in momentum eq above.
Im not sure. Can anyone help.
Thankx