Recent content by pluspolaritons

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    How Does Δml=0 and Δl=±1 Apply in Quantum Mechanics?

    The selection rules state that: Δl=±1 Δml=0,±1 I can't figure out a case where Δml=0 and Δl=±1, can anyone help by giving an example? Thanks.
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    Understanding Forces: Explaining maa and mbb in a Simple Example"

    Thanks, I think it's clearer now. So, F only acts on A but not B right? This is because F is in direct contact with A but not B, correct? But since B is in direct contact with A, it will feel the force of A on B.
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    Understanding Forces: Explaining maa and mbb in a Simple Example"

    Thanks Andrew. I know the solution to this problem, but I need to know what is maa and mba. Why is the force of A on B equals to mba instead of maa? Then what is maa?
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    Understanding Forces: Explaining maa and mbb in a Simple Example"

    Hi, Please take a look at this figure: Screenshot by Lightshot There is a force that is applied so that block B will not fall under the influence of gravity. I have set up the problem as: F= (ma+mb)a μR=mbg where μ is the coefficient of friction and R is the reaction force...
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    Why Does a Coin Fly Off a Turntable?

    What I meant is shouldn't the friction force be in the opposite direction of the centripetal force (i.e pointing outward)? I thought that was the definition of friction.
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    Why Does a Coin Fly Off a Turntable?

    technician - i didn't mean that the coin will fly away from the center, but just simply it will fly away. 256bits/technician/rcgldr - It is possible that the coin will return to circular path if the turntable is big enough. But once the static friction is overcome it takes less force to keep...
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    Why Does a Coin Fly Off a Turntable?

    Shouldn't the friction force always be in a direction opposite to the force applied? In this case the force is the centripetal force and the friction force should be in a direction opposite to the centripetal force?
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    Why Does a Coin Fly Off a Turntable?

    OK here's an after thought, please let me know if I'm correct: Maybe the coin does in fact go towards the center. But the point is it is no longer in a circular path, so it will eventually fly off the turntable once the static friction is overcome.
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    Why Does a Coin Fly Off a Turntable?

    If I put a coin on a turntable at some distance away from the center and start turning the turntable eventually there will be a speed where the coin will fly off from the turntable. If we put this into calculation. We will equate the centripetal force and static friction to find out the...
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    Conservation of Angular Momentum of a stick

    What about rotational angular momentum, e.g a disc that is rotating. Does the angular momentum depends on where my point of reference is?
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    Understanding the Physical Meaning of Orthogonality Condition in Functions

    @ModusPwnd - I should have written 'wavefunctions' instead of 'functions'. Anyway, I found a pretty good website that helps to explain this a bit: http://quantummechanics.ucsd.edu/ph130a/130_notes/node140.html So from what I understand, In QM, if we want our observable to be real and...
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    Understanding the Physical Meaning of Orthogonality Condition in Functions

    What does it mean when we say that two functions are orthogonal (the physical meaning, not the mathematical one)? I tried to search for the physical meaning and from what I read, it means that the two states are mutually exclusive. Can anyone elaborate more on this? Why do we impose...
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    Conservation of Angular Momentum of a stick

    Oh right, I was thinking the pivot is at the end of the stick. Ok you're right, the pivot should be at the center of mass. Good catch, I didn't notice I was using 'L' for two different things. Thanks for pointing that out. Thanks again!
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    Conservation of Angular Momentum of a stick

    Hi, I think I understood the problem now thanks to cepheid. I was assuming that the angular momentum of the particle is zero at all point without using any reference point.
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