Recent content by sdfsfasdfasf

  1. S

    Flux linking (and de-linking?)

    I agree its a correct statement, however my interpretation (incorrect) was that "links to" refers to increasing flux exclusively. When we cut the current, that reduces the flux present right?
  2. S

    Flux linking (and de-linking?)

    My confusion was around the phrase "links to", if instead we use "flux in A is linked to B" that makes a lot more sense to me. I was misunderstanding and thought "links to" had something to do with increasing flux, when it dosesn't. Thank you Steve.
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    Flux linking (and de-linking?)

    I wasn't answering the question in my post! I just wanted to know what is meant by the phrase "links to", and it seems that its a little more complicated than expected, could you talk about it a little more, particularly the bit where you said "this is always true". How can we distinguish this...
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    Flux linking (and de-linking?)

    Initially the current is non-zero therefore we have a magnetic field present, and at the end there is no current therefore there is no magnetic field present. When we open the switch, and the current drops to 0, there is a change in the magnetic flux of B, as the field from A has gone. This...
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    I am confused about air density/drag

    OCR A was a difficult paper but I think I did good, if I just focus on paper 2 and 3 I should be able to get my A*. Further Maths was surprisingly easy however, so unsure what the 2nd paper will look like for that.
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    I am confused about air density/drag

    Yeah I looked it up and found a higher level equation that uses some fancy Reynolds number (proportional to density) and the density term itself, thereby showing that the drag decreases by a greater factor than the thrust (for a given velocity) if you decrease the density, thereby showing the...
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    I am confused about air density/drag

    I don't know what you mean by that, my specification does not reference the specifics. I have an exam tomorrow and I'd like to get this sorted, do you have any reading information or could you kindly tell me the answer? Thank you
  8. S

    I am confused about air density/drag

    Drag decreases for a fixed velocity as air density decreases, thrust decreases as air density decreases. How do I link less drag and less thrust to a higher velocity?
  9. S

    I am confused about air density/drag

    Part a) Is fairly trivial, just multiply both the given numbers to find the total change in momentum per second, which by Newtons II/III law is the thrust produced. Part d) is confusing me a great deal. I agree that pressure/density of air will decrease with altitude, this means that there will...
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    Confusion about variables in polar coordinates

    My confusion refers to this question above. If I were to ask you, what is the equation of the radial line, what would you say? I know that the general equation the radial line with cartesian gradient of m has an equation of θ = arctan(m). Clearly here the angle between the radial line and...
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    Chemistry Colour of Fe3+

    The joys of chemistry.
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    Chemistry Colour of Fe3+

    It's just strange because my textbook (from which this exam question is based off) claims that hydrated Fe3+ is yellow, and all other exam questions on this topic use that piece of information, its just this one that says its brown.
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    Vertical circular motion

    Wonderful, thank you so much, Orodruin.
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    Chemistry Colour of Fe3+

    I've been tasked with writing an equation to show the reaction of the Fe2+ complex with Cl2. I believe that the oxidation state of the Iron has changed, so I would write 2Fe(H2O)(6)^2+ + Cl2 -> 2Cl- + 2Fe(H20)(6)^3+, but I can't be sure this is correct. Is the 2Fe(H20)(6)^3 ion not yellow in...
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    Vertical circular motion

    So the resultant (centripetal) force varies, correct? As the velocity's magnitude varies throughout the loop.
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