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HNQ
3:41 AM
1
Q: How does a twisted piece of string/yarn wind back on itself? What kinds of forces are responsible for this?

NicholasI do a lot of fibrework (carding wool, spinning yarn, weaving, etc.) and I've noticed a funny behaviour that anything long and flexible, which can withstand significant torque exhibits. If I take a piece of yarn and begin to twist it, it remains twisted so long as I keep it in tension (the piece ...

 
 
1 hour later…
HNQ
4:43 AM
2
Q: What's the physical meaning of the standard base vectors?

SimoBartzI can find 3 displacement $\vec d_1 ,\vec d_2, \vec d_3$ and use them as basis so that a displacement is $\vec d=a\vec d_1 +b\vec d_2+c \vec d_3$. I can find 3 forces $\vec F_1 ,\vec F_2, \vec F_3$ and use them as basis so that a force is $\vec F=a\vec F_1 +b\vec F_2+c \vec F_3$. So the basis are...

 
 
17 hours later…
HNQ
9:31 PM
2
Q: Why do the expressions for an object rolling down an incline not depend on the coefficient of static friction?

Ibrahim SyedIn my physics course, we are doing an experiment rolling disks and spheres down an incline (assuming there is no slipping). In doing the derivations (assuming a moment of inertia of $\frac25mR^2$ for sphere and $\frac12mR^2$ for disk) I have derived that the final velocity should be $\sqrt{\frac{...

 
 
1 hour later…
HNQ
10:52 PM
4
Q: Electric field due to a hydrogen atom

Utkarsh SharmaElectric field due to two opposite charges According to the answers in the previous questions, if you separate the two charges from each other, they will produce a non-zero electric field everywhere in space. (This field will get very weak, but still non-zero, at locations much further from ...

 

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