Recent content by trumpsnuffler

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    Airplane Range in North Wind: Prove and Max Value

    sorry, still getting to grips with using this forum. t1 and t2 were meant to be written in subscript..
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    Airplane Range in North Wind: Prove and Max Value

    oh wow. no idea why i didn't think of that.. :blushing: okay. so cos² = 1 - sin² cos² = 1 - sin² = 1 - [(n/v)sin(φ)]² = 1 - (n²/v²)sin²(φ) therefore cosθ = √[1 - (n²/v²)sin²(φ)] is the above expression the value of [t][/1] then? and [t][/2] = the same, but a positive...
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    Airplane Range in North Wind: Prove and Max Value

    okay. as (n/v)sin(φ) = sin(θ) (n/v)cos(φ) = cos(θ) wasn't too sure if i could make this jump, but bearing in mind that the graphs of sin and cos are so similar, surely the above expression for cos(θ) holds to be true?
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    Airplane Range in North Wind: Prove and Max Value

    and with regards to the second part of the question 'find the maximum range and for which direction', would i have to go through the normal means of finding a maximum (i.e differentiating), and if so, differentiating with regards to what? or do i just have to make n²sin²φ = 0, which would give...
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    Airplane Range in North Wind: Prove and Max Value

    morning all, opted to get an early night in favour of an early rise! okay, the above vector diagram's a bit misleading. on the return journey, the plane doesn't necessarily come fly off westwards to form a right angled triangle with Q v and n. right the x and y components for the...
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    Airplane Range in North Wind: Prove and Max Value

    hmmm, okay, would the time be calculated via pythagoras's theorem for the individual x and y components of v and n, for each journey repectively? (n/v)sin(φ)..? i'm a bit lost, i can see why the numerator is R(v+n)(v-n) and i can see that the v on the denominator comes from R/v, but i...
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    Airplane Range in North Wind: Prove and Max Value

    hmm. what is this new variable S...? (sorry to be so slow, please be patient with me!)
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    Airplane Range in North Wind: Prove and Max Value

    i think at the rate this question is taking me, you might break 15,000 posts by the end tim...
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    Airplane Range in North Wind: Prove and Max Value

    so would this be the (v + n) from the journey there, and then (v - n) for the journey back? or (v - n) for the way there, and (v + n) for the way back (now i know that a north wind blows north and not south...)
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    Airplane Range in North Wind: Prove and Max Value

    the vectors leading to Q? i.e. v and n?
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    Airplane Range in North Wind: Prove and Max Value

    hmmm. latex doesn't seem to work for me..
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    Airplane Range in North Wind: Prove and Max Value

    isn't it just the same? the angle made from the north axis to the resultant vector Q (in the return journey) must be φ in order for the plane to return to its original place. so, from this, and the 'z rule' of angles, the top angle, between n and Q must therefore be equal to φ. so...
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    Airplane Range in North Wind: Prove and Max Value

    sorry for the delay in a reply, had to drop my housemate off to pick up his car. okay, so from the sine rule, i get: sin (180-φ)/v = sin(C)/n and from this, so C = arcsin(nsin(180-φ)) <-------- can this be canceled to give n(180-φ)? and then the final angle is just 180 - (180 - φ) - the...
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    Airplane Range in North Wind: Prove and Max Value

    hmmm, I'm not too sure I'm either a) working out the angles correctly, or b) working out the correct angles.. but okay. the angles i got for the internal angles of triangle vQn are: the angle between n and Q is (180 - φ) then the angle at the top, called, say, A, between v and n...
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    Airplane Range in North Wind: Prove and Max Value

    hmmm, I'm not too sure I'm either a) working out the angles correctly, or b) working out the correct angles.. but okay. the angles i got for the internal angles of triangle vQn are: the angle between n and Q is (180 - φ) then the angle at the top, called, say, A, between v and n, through use...
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