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    http://pmt.physicsandmathstutor.com/...%20Edexcel.pdf

    Hi. Could someone help out in explaining me question 13(d) by telling me that how it's done? I have an exam on the 17th(Tuesday) for the International Advanced Level by Edexcel. Was doing this paper as one of my mocks so need help in understanding this.

    http://pmt.physicsandmathstutor.com/...%20Edexcel.pdf

    Question 13(b and d), how do we prove this expression exactly? And how is part c linked with part d?
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    (Original post by sabahshahed294)
    http://pmt.physicsandmathstutor.com/...%20Edexcel.pdf

    Hi. Could someone help out in explaining me question 13(d) by telling me that how it's done? I have an exam on the 17th(Tuesday) for the International Advanced Level by Edexcel. Was doing this paper as one of my mocks so need help in understanding this.

    http://pmt.physicsandmathstutor.com/...%20Edexcel.pdf

    Question 13(b and d), how do we prove this expression exactly? And how is part c linked with part d?
    Express the height of the passenger given to you in the question, in the form deduced in a).

    Pick and arbitrary height/location (part c) has chosen H = 18). For instance, take the bottom of the Ferris wheel where:

    H = 0.

    Solve your equation to find the times where the passenger will be at the bottom. Since, the height of the passenger is periodic there will be an infinite number of times this happens.

    Simply observe the period it takes for the passenger to pass the same height twice.

    At this point, you should realise that there was a reason why choosing H = 0 simplifies the problem.
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    13(d) is relatively simple. let's say, for simplicity, that H = cos(x) - sin(x). H is gonna repeat itself everytime x reaches 360 right?

    Your equation is H = ...cos(30t + ...). This will have the same value for 30t = 0 and 30t = 360 and 30t = 720 etc. Therefore for one revolution:

    30t = 360
    t = 360/30 = 9 mins

    Therefore 2 revs takes 18 mins
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    (Original post by pleasedtobeatyou)
    Express the height of the passenger given to you in the question, in the form deduced in a).

    Pick and arbitrary height/location (part c) has chosen H = 18). For instance, take the bottom of the Ferris wheel where:

    H = 0.

    Solve your equation to find the times where the passenger will be at the bottom. Since, the height of the passenger is periodic there will be an infinite number of times this happens.

    Simply observe the period it takes for the passenger to pass the same height twice.

    At this point, you should realise that there was a reason why choosing H = 0 simplifies the problem.
    Got it. Thank you!

    (Original post by Darth_Narwhale)
    13(d) is relatively simple. let's say, for simplicity, that H = cos(x) - sin(x). H is gonna repeat itself everytime x reaches 360 right?

    Your equation is H = ...cos(30t + ...). This will have the same value for 30t = 0 and 30t = 360 and 30t = 720 etc. Therefore for one revolution:

    30t = 360
    t = 360/30 = 9 mins

    Therefore 2 revs takes 18 mins
    Alright. Thank you. Btw, it's 1 revolution takes 12 min but yeah, I understood what you did. Thanks for the help.
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    (Original post by sabahshahed294)

    Alright. Thank you. Btw, it's 1 revolution takes 12 min but yeah, I understood what you did. Thanks for the help.
    Haha, my bad :P
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    (Original post by Darth_Narwhale)
    Haha, my bad :P
    lol. Happened many times with me Once wrote 4 multiplied by 2 as 16 while solving papers xD
 
 
 
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