Calculating Space Shuttle Velocity: Astronaut Melroy's Historic Flight

[beachbabe0191]

Homework Statement

Problem Statement: Astronaut Pam Melroy, history's 3rd woman space shuttle pilot, flew the space shuttle discovery to the International Space Station to complete construction in October of 2000. To undock from the space station, Pilot Melroy released goooks holding the 2 spacecraft together and the 68 000-kg shuttle pushed away from the space station with the aid of 4 large springs.
A) if the 73 000-kg space station moved back at a speed of 0.50 m/s, how fast and in what direction did the space shuttle move?
B) What was the relative speed of the 2 spacecraft as they separated?M_{1}= 68 000-kg
V_{1F}= ?
M_{2}= 73 000-kg
V_{2F}= -0.50 m/s
V_{o}= 0 m/s

Homework Equations

(M_{1} + M_{2}) V_{o} = M_{1}V_{1F} + M_{2}V_{2F}

The Attempt at a Solution

(68 000-kg + 73 000-kg)0 m/s = ((68 000-kg)( V_{1F} ) + (73 000-kg)(-0.50 m/s)

0 = (68 000-kg)V_{1F} - 36 500-kg \timesm/s
add -36 500-kg \timesm/s to 0

36 500-kg \timesm/s = (68 000-kg)V_{1F}

= 0.53676 m/s

BUT the back of the book for this odd says
1.04 m/s

 

[beachbabe0191]

needs help very very very fast

 

[mgb_phys]

It is asking you the speed they separate, remember that the ISS is also moving so it is the total speed between them.
You have worked out the speed of the shuttle from the starting point.

 

[beachbabe0191]

It is asking you the speed they separate, remember that the ISS is also moving so it is the total speed between them.
You have worked out the speed of the shuttle from the starting point.

so my answer is the initial velocity??

 

[mgb_phys]

No the answer is 0.5m/s for the iss plus 0.53676 m/s for the shuttle
So the velocity they are moving apart is 0.5 + 0.53676 = 1.04m/s