- #1
queenspublic
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When doing Angular Momentum, how is it that 2.0(2.12i + 2.12j) x (-3.863i - 1.035j) is equal to 2.0[-2.194k + 8.189k]?
Understanding Angular Momentum: A Brief Explanation of Vector Cross Products
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The discussion centers on the calculation of angular momentum using vector cross products. Participants clarify that the cross product of unit vectors i and j results in k, while the reverse yields -k. The specific example of calculating 2.0(2.12i + 2.12j) x (-3.863i - 1.035j) is explored, leading to the conclusion that it simplifies to 2.0[-2.194k + 8.189k]. The conversation emphasizes understanding the foundational rules of vector multiplication to grasp the final results. Overall, the exchange highlights the importance of clarity in vector operations.
- #2
tiny-tim
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'cos i x j = k and j x i = -k (and ii = jj = 0) 
- #3
queenspublic
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tiny-tim said:'cos i x j = k and j x i = -k (and ii = jj = 0)
I don't understand.
cos i x j = k ?
So cos 2.12i x 2.12j = -2.194k ?
Please explain it in numbers. How do I get -2.194k + 8.189k ?
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tiny-tim
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queenspublic said:
he he
no, I meant because i x j = k
- #5
queenspublic
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tiny-tim said:he he
no, I meant because i x j = k
O! I get it! Thanks.
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