wrobel's latest activity
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wrobel replied to the thread A How does time derivative commute from one variable to another?.In order for simplicity sake some authors make the narration harder. By definition the kinetic energy of a particle is... -
wrobel replied to the thread Motion in 2 dimensions.The point of JimWhoKnew can be illustrated by the following simple analogy. Consider an initial value problem ##\dot x^2+x^2=1,\quad...
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Since this problem came about as an off topic, I feel uncomfortable to hijack the thread. Even more so when the OP places a picture of a...
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wrobel replied to the thread Motion in 2 dimensions.Bring the proofs please.
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wrobel replied to the thread Motion in 2 dimensions.
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wrobel replied to the thread Collision of a bullet on a rod-string system: query.The point P is a point of the lab system that coincides with the end of the rod before the collision. If the collision happens at the...
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wrobel replied to the thread Angular Momentum- Conserved or not?.I do not know what OP means. I do not see equations of motion for the system of 3 degrees of freedom and I do not see a derivation of...
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wrobel replied to the thread Angular Momentum- Conserved or not?.In #1 the rod AB is fixed relative the lab frame. The system has 2 degrees of freedom. I suggested a system with 3 degrees of freedom.
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wrobel replied to the thread Angular Momentum- Conserved or not?.It is interesting to answer the same question assuming that the rod AB can rotate freely about the vertical axis
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wrobel replied to the thread Angular Momentum- Conserved or not?.The original statement of the problem is that the rod AB can not rotate so there must be a torque that keeps it at rest. I don't see any...
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wrobel replied to the thread Angular Momentum- Conserved or not?.If the rod AB can rotate freely about the vertical axis then the projection of the angular momentum of the whole system on the vertical...
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wrobel replied to the thread Angular Momentum- Conserved or not?.I do not think that the angular momentum of the whole system about the vertical axis is conserved because of this:
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Short answer: yes. You can perhaps take a peek at a recent study to get a feeling for the numbers involved...
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In science fiction movies (Interstellar for example) people organize a rotation of a spacecraft to provide an artificial gravity by...
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wrobel replied to the thread B What could prove this wrong? I'm having a dispute with friends.Old thread but it dives up as a hot thread every time . I just want to say that there are several definitions of arc length. Math...
