(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A spaceship is coasting with a constant velocity of 124 m/s. The ship fires a deep space "care package" of mass 1300 kg. The firing of the care package brings the rocket ship to a halt. If the mass of the spaceship, not including the rocket, is 4.0 x 10^{6}kg, what is the launch speed of the package?

2. Relevant equations

p=mv

ΣP_{i}=ΣP_{f}

P_{iS}=m_{s}v_{s}

P_{iP}=m_{p}v_{p}

P_{fS}=m_{s}v_{s}

P_{fP}=m_{s}v_{s}

ΣP_{i}=P_{iS}+P_{iP}

ΣP_{f}=P_{fS}+P_{fP}

final equation: m_{S}v_{iS}+m_{P}v_{iP}=m_{S}v_{fS}+m_{P}v_{fP}

where s=spaceship and p=package

3. The attempt at a solution

m_{S}=4.0 x 10^{6}kg

v_{iS}=124 m/s

v_{fS}=0

m_{P}=1300 kg

v_{iP}=?

v_{fP}=?

I do not know if the final equation used is correctly applied. After plugging in all of the known variables, there are two unknown. Could someone point me in the general direction?

Thank you for your time and help.

-D. Tran

**Physics Forums | Science Articles, Homework Help, Discussion**

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Launch speed of the package?

**Physics Forums | Science Articles, Homework Help, Discussion**