How Do You Calculate Original Velocity from Momentum in a Two-Spacecraft System?

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To calculate the original velocity of two linked spacecraft after they are thrust apart, the momentum of each spacecraft must be determined using P=mv, with velocities resolved into component vectors. The total momentum is calculated by adding the x-components of each spacecraft's momentum, ensuring that the original total momentum is conserved. The total mass of the linked spacecraft is also considered for accurate calculations. While converting velocities from km/h to m/s is common practice, it may not be necessary if the final answer is acceptable in km/h. The steps taken in the calculation appear correct, focusing on momentum conservation principles.
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spacecraft that are linked together are then thrust apart by large springs,

S1 has a mass of 1.9x10^4 kg, then has a velocity of 3.5x10^3km/h at 5.1 degrees to the original direction..

S2 has a mass of 1.7x10^4kg and a velocity of 3.4x10^3km/h at 5.9 degrees to the original direction.


I just want to double check to make sure I solved this correctly.


3. I converted km/h into m/s. Then I calculated each spaceships momentum using P=mv and resolved each spaceship into its own component vector.

I figured the X in each component vector would add up to the original total momentum of the 2 spaceships when they were linked together, because Pt = P1+P2

I solved each x compenent using X=Pcos(theta) then I added them together to get the total momentum.

I also added the mass of the two spaceships together to get the total mass when they were linked together.

Using both of these values I used P=mv to calculate the original velocity of the two spaceships when they were linked together.

I'm not worried about any math errors, just the errors in any steps that I took. Thanks a lot.
 
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Looks good!

By the way, it's probably not necessary to convert the velocities into m/s. Since they were giving you km/h velocities, that more or less implies that an answer in km/h is acceptable.
 
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