1. The problem statement, all variables and given/known data 80 kg astronaut carrying a 20kg tool kit is initially drifting toward a stationary space shuttle with a speed of 2 m/s. If sh throws the tool ki toward the shuttle with a speed of 6 m/s as seen from the shuttle, her final speed is? 2. Relevant equations If it is seen from the shuttle, does that mean the 6 m/s is a negative or a positive? 3. The attempt at a solution I used the Conservation of Linear Momentum m1Vf1 + m2Vf2 = m1Vo1 + m2Vo2 Vf1 = (m1Vo1 + m2Vo2 - m2Vf2) / m1 = [(80*2) + (20*2) - (20*6)] / 80 = 1 m/s **If I use a -6 instead, the answer is 4 m/s. Which is right?