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# Why do they divide by 2kg and not 1kg (momentum)? watch

1. Question:

Two identical objects each of mass 1kg collide. After the collision teh loss of momentum for one of the objects is 120kgms^-1.

They rearrange deltap = mv. But the thing is they use mass as 2kg, two of the objects why not 1kg? Surely its the momentum of one object?
2. (Original post by BrainJuice)
Question:

Two identical objects each of mass 1kg collide. After the collision teh loss of momentum for one of the objects is 120kgms^-1.

They rearrange deltap = mv. But the thing is they use mass as 2kg, two of the objects why not 1kg? Surely its the momentum of one object?
Can you post a picture of the exact question please?

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3. Thank you boss

(Original post by Kyx)
Can you post a picture of the exact question please?

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4. (Original post by BrainJuice)

Thank you boss
OH I'm so sorry! They wrote 2kg, I thought hey wrote 1kg! Thank you nevertheless
5. Because they each have a mass of 2, you misread!
6. (Original post by BrainJuice)

Thank you boss
The mass is 2kg, not 1kg

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