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    Anyone here plzzz need help with mechnics....
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    ....Okay? What exactly do you need help with? You haven't provided us with a question.
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    I am confused about this question......Name:  m3.png
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    so the bit I am confused about is why did they times it by 2? and also ehy h=0 and they divided by the acceleration why???
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    HELOOOOOOOOOOOOOOOOOOOO any one???????????????????
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    I NEED HELP!!! plsssss someone help me with mechanics I am failing
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    (Original post by eden3)
    ....Okay? What exactly do you need help with? You haven't provided us with a question.
    I posted the question so can u help now?
    plssssssss
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    (Original post by Hard work)
    I posted the question so can u help now?
    plssssssss
    Calm down.. I haven't done A-levels since last June so it's taking me a while to figure out.
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    (Original post by Hard work)
    I NEED HELP!!! plsssss someone help me with mechanics I am failing
    I'm sorry I only understand the alternative answer.
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    (Original post by Hard work)
    I am confused about this question......Name:  m3.png
Views: 191
Size:  148.9 KBAttachment 516003516005

    Vertical Motion (initial speed) = 40sina

    Recall the equation s=ut+1/2at^2 but as it is decelerating it becomes s=ut-1/2at^2.

    Note that in this case a is interchangable with g as it is acceleration due to free fall.

    So next you rearrange for t:

    s=0 as there is no displacement so you can rule that out.

    Add 1/2gt^2 on both sides leaves 1/2gt^2=ut
    The t's on both sides cancel out leaving 1/2gt=u
    Times both sides by 2 to give you gt=2u
    Then divide both sides by g so t=2u/g
    Then just substitute T= 2x40xsina/g


    T=80sina/g
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    Name:  M1-Projectiles.png
Views: 174
Size:  312.0 KBTry this, I hopefully simplified enough. Ignore my terrible handwriting.
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    As for the second half of the question it is just Speed=Distance/Time
    So we rearrange for D giving D=ST where D is Rm.

    Use cos to calculate the horizontal motion (initial speed) which is 40cosa.

    R=ST so you now have R=40cosaxT
    You know that T=80sina/g from the first part of the question so you just substitute giving...
    40xcosax80xsina/g
    40x80=3200
    Final Answer: 3200sinacosa/g
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    (Original post by Hōseki)
    Vertical Motion (initial speed) = 40sina

    Recall the equation s=ut+1/2at^2 but as it is decelerating it becomes s=ut-1/2at^2.

    Note that in this case a is interchangable with g as it is acceleration due to free fall.

    So next you rearrange for t:

    s=0 as there is no displacement so you can rule that out.

    Add 1/2gt^2 on both sides leaves 1/2gt^2=ut
    The t's on both sides cancel out leaving 1/2gt=u
    Times both sides by 2 to give you gt=2u
    Then divide both sides by g so t=2u/g
    Then just substitute T= 2x40xsina/g


    T=80sina/g
    Beat me to it, aha
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    (Original post by TheTechnoGuy)
    Beat me to it, aha
    :happy2:
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    (ii) Calculate the acceleration of the car and trailer. Calculate also the force in
    the coupling, stating whether this is a tension or a thrust. [6]

    Newton's second Law F=ma

    Add the masses: 1500+900=2400kg
    Driving force = 600N
    F=ma
    600N=2400kgxa
    A=0.25m/s^2

    For calculating the Tension you also use F=ma
    Where F is the tension.
    T=900kgx0.25m/s^2
    T=225N
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    Thanks so much guys really appreciate it.
    I have another question I am struggling with,
    1. Ann and Beryl are both pushing a piano. Ann pushes in the direction 4i + 3j andBeryl in the direction 12i + 5j, where i and j are the standard unit vectors.Together they produce a force of (68i + 33j) N so that p(4i + 3j) + q(12i + 5j) = 68i + 33j, where p and q are constants.Calculate the force with which Beryl pushes.
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    (Original post by Hard work)
    Thanks so much guys really appreciate it.
    I have another question I am struggling with,
    1. Ann and Beryl are both pushing a piano. Ann pushes in the direction 4i + 3j andBeryl in the direction 12i + 5j, where i and j are the standard unit vectors.Together they produce a force of (68i + 33j) N so that p(4i + 3j) + q(12i + 5j) = 68i + 33j, where p and q are constants.Calculate the force with which Beryl pushes.
    I believe it's a simultaneous -
    4p + 12q = 68
    3p + 5q = 33

    Take it from here and find the values for p and q.
 
 
 
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