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    Resources with learning strategies for students of physics

    Thanks for the interesting info. This is useful. I'll check out the book by Schoenfeld. I am a mechanical engineering major. I had a short stint as a research scholar in a dept of theoretical physics, but I dropped out after two years. I currently coach students of my town for math and physics...
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    Resources with learning strategies for students of physics

    Thanks, I see your point. Will wait for it to be moved.
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    Resources with learning strategies for students of physics

    My apologies. I did look at various forums to decide where this belongs, but most of the threads on academic guidance forums seemed to be on courses and specific topics, and not studying in general. But now I see there are posts on 'learning' as well. I also wondered whether I should post it in...
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    Resources with learning strategies for students of physics

    Thanks. Just to be clear, I am not asking for shortcuts to study physics without any hard work. I am looking for tips for more efficient learning, which is why I gave the examples above. I have noticed that different students, who seem to put in the same amount of effort, end up with different...
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    Resources with learning strategies for students of physics

    I can find several resources (in this forum and elsewhere) on pedagogy and teaching tips that are geared towards teachers. Are there any books or resources that provides tips for students of physics, that would make learning more efficient and effective? Examples of the kind of things I am...
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    Adiabatic approximation in the derivation of the speed of sound

    Thanks. I get that it matches the observed speed of sound. I am just curious as to why? Was there a way we could have guessed beforehand that it would work?
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    Adiabatic approximation in the derivation of the speed of sound

    How do we know that this case satisfies that condition? Is there a practical limit below which a process can be reasonably assumed to be quasistatic? I have read that we can make the quasistatic approximation for expansion and compression processes, if the boundaries are moving much slower than...
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    Adiabatic approximation in the derivation of the speed of sound

    The speed of sound in a gas at temperature T is given to be ## v=\sqrt{\frac{\gamma RT}{M}}##, where ##\gamma## is the adiabatic exponent, R is the gas constant and M is the molar mass of the gas. In deriving this expression, we assumed that the compression and expansion processes were so fast...
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    Propagation of errors: two different results for same question

    I see. So if I assumed du and dv to be positive in the first two terms, then they must remain positive in the last term. So the negative sign remains negative. In general, if the numbers were different, and if I want to do it the first way, to find the maximum error, should I try different...
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    Propagation of errors: two different results for same question

    I am sorry, the question got posted before I could type it out completely. I have updated it.
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    Propagation of errors: two different results for same question

    If I write ##f=\frac{uv}{u+v}## and then take differentials on both sides, I get ##\frac{df}{f}=\frac{du}{u}+\frac{dv}{v}+\frac{du+dv}{u+v}##, I get the fractional error as 0.03. (I have replaced the negative signs that come as a result of quotient rule with positive signs, since we are asked to...
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    How do temperatures add?

    Ok. I'll avoid such questions in the future. Thanks for the help.
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    How do temperatures add?

    Thank you. That makes complete sense. Having a magnitude and direction is an intuitive way of thinking about certain vector quantities we encounter in high school physics, but is not the definition of a vector. And it isn't even the best way to describe vectors even in physics. How would you...
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    How do temperatures add?

    Ok. Thanks.
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    How do temperatures add?

    I agree that it is indeed a misapplication. I used it as an example of a misapplication. I was trying to show that even though velocity is a vector, adding velocities of two different objects does not make sense, even though you can in principle add two vectors. Please note the sentence, 'But...
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    How do temperatures add?

    Well, I did make an attempt to answer the question: The resultant temperature when you mix two substance is not what 'adding temperatures' means. I thought the above example must be convincing. Moreover, the description I gave of vectors and scalars are not my own, but from the prescribed...
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    How do temperatures add?

    The students actually did know through intuition that temperature, upon mixing, should NOT just add up. Their question was, since we know that they just don't add up like masses do, how can we still call them scalars.
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    How do temperatures add?

    I am trying to describe vector and scalar physical quantities, without defining vectors and scalars mathematically. I think I understand. We are mapping on physical quantities to the abstract concept of vectors. So we can perform whatever operations are defined on vector spaces on these...
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    How do temperatures add?

    I understand. I know about heat capacity, but this is a question asked by students when discussing vectors and scalars. And I gave them the example of person in Africa and U.S. displacement that I mentioned in the original post, to show that one could blindly add two quantities as vectors or...
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    How do temperatures add?

    So it is in terms change in temperature, that we can talk of addition : T+ΔT, where T=300 K and ΔT= 30 K would only give 330K ,and nothing else. That is good. Thanks. There is a small issue of decrease in temperature though. Distances, which are scalars, only increase and never decrease during...
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    How do temperatures add?

    So the only argument that can be given to argue that temperature is a scalar is to say that it doesn't have a direction?
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    How do temperatures add?

    I was going through vector and scalar quantities (the way they are taught in high school), and this is how I think students are supposed to understand it: Scalar quantities are quantities that add like numbers. For e.g. Mass. If I add 100 g of water to a bucket and then add a further 100 g, I...
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    Propagation of transverse pulse on a string

    In the first case, they would meet at the midpoint again. In the 2nd case, if say the pulse was initially at a distance d from one boundary, then after an even no. of reflections, they will meet at the same initial position of the pulse. After an odd no. of reflections, they will meet at a...
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    Propagation of transverse pulse on a string

    Assuming there are no losses (Reflection coefficient is 1), they are inverted and reflected. Shape and size of the pulses remains the same, propagation speed remains the same (since it is a property of the medium). So the pulses just bounce about, inverting at each reflection. And whenever and...
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    Propagation of transverse pulse on a string

    Homework Statement A horizontal string at tension T is tapped at the midpoint to create a small transverse pulse. What happens to the pulse as time passes? If the pulse is instead created at a point other than the midpoint, what happens to it? Neglect damping. Homework Equations Speed of...
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    Pulling/pushing an elastic rod at high speeds

    Strange things will happen in case we stick to the perfectly elastic material model. if we push one end of the rod with v=c, it will reach where the other end is, even before the other end starts to move. So the rod is effectively reduced to zero volume. (If v>c, I can't even imagine!) Of...
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    Pulling/pushing an elastic rod at high speeds

    Ah. Thanks. Lateral deformation makes sense. The simulation was interesting. In the opposite process of pulling (extension), what will happen? Will the object certainly break?
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    Pulling/pushing an elastic rod at high speeds

    Consider an elastic rod lying on a table. If one end of the rod is pulled/pushed along the length of the rod with speed v, the other end will not immediately start moving, because any disturbance takes time to propagate along the rod. To be precise, the other end will move after a time t=L/c...
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