Schedule ... no Jim on Thursday. Alternatives?
Questions about homework or anything else?
Sometimes called "linear momentum" (to distinguish it from "angular momentum".)
I would expect the text to cover this here but apparently they wait until the rotations chapter :center of mass (i.e. average over masses position).
related topics :
... has been posted.
In quantum physics, the momentum of a particle is related to its wavelength when that particle acts like a wave. This leads to the notion that there is a fundamental uncertainty between position and momentum - that the two concepts cannot be defined exactly for the same particle at once.
In the fundamental math of physics, the symmetry of the equations of motion under spatial translation is what leads to the conservation of momentum.
In a (very) similar way, the energy of a quantum particle is related to its frequency (vibrations per second) when it acts like a wave. That leads to the notion that there is a fundamental uncertainty between energy and time - that the two concepts cannot be defined exactly for the same particle at once.
See for example wikipedia: uncertainty principle
where \( \hbar \) is a constant - Plank's constant over two pi,
and the \( \Delta \text{foo} \) is the uncertainty inherit
in trying to measure any quantity foo.
It's interesting that in our starting definitions, space and time show up connected to the other concepts, not to the "complentary" ones in quantum physics.
I've attached the .txt file and .pdf notepad from my blackboard scrawling.
And I've uploaded a recording of today's meeting; check out the link on the left.
![[paper clip]](/cours/static/images/paper_clip_tilt.png)
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center_of_mass.txt | Thu Apr 18 2024 02:37 am | 960B |
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center_of_mass_notepad.pdf | Thu Apr 18 2024 02:37 am | 341K |
