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    Particles p and q of masses 2m kg and m kg respectively are attached to the ends of a large and inextensible string which passes over a smooth fixed pulley. They both hang at a distance of 2 meters above horizontal ground. The system is released from rest.
    Given that the particle Q does not reach the pulley:
    Find the greatest height that Q reaches above the ground
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    (Original post by allegrosquir)
    Particles p and q of masses 2m kg and m kg respectively are attached to the ends of a large and inextensible string which passes over a smooth fixed pulley. They both hang at a distance of 2 meters above horizontal ground. The system is released from rest.
    Given that the particle Q does not reach the pulley:
    Find the greatest height that Q reaches above the ground
    Great.

    You tried anything, or do you want us to do this Q for you?
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    I found that a=3.3 and v=3.6 (speed of p when it hits the ground) . I checked my solutions ant they are right.
    I tried to do the question. But my answer is wrong. I think that u=0 as they are released form rest and v=3.6 and a=3.3. So the answer should be 3.96( 1.96+2). But it is wrong.
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    (Original post by RDKGames)
    Great.

    You tried anything, or do you want us to do this Q for you?
    My reply is above
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    (Original post by allegrosquir)
    My reply is above
    Can you post your working?
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    (Original post by RDKGames)
    Can you post your working?
    Here
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    (Original post by RDKGames)
    Can you post your working?
    Is there anything wrong with the working?
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    (Original post by allegrosquir)
    Is there anything wrong with the working?
    When P hits the floor, Q becomes a projectile upwards. If the final speed of P is 3.6 then the initial speed of the projectile Q is 3.6 upwards. You must treat Q as a projectile now and find the highest it goes.
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    (Original post by RDKGames)
    When P hits the floor, Q becomes a projectile upwards. If the final speed of P is 3.6 then the initial speed of the projectile Q is 3.6 upwards. You must treat Q as a projectile now and find the highest it goes.
    Does the final speed of equal to 0?
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    (Original post by allegrosquir)
    Does the final speed of equal to 0?
    Yes.
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    (Original post by RDKGames)
    Yes.
    But then the distance will be negative?
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    (Original post by allegrosquir)
    But then the distance will be negative?
    Well it shouldn't be. You need to pick g=-9.8 and assume upwards as the +ve direction and you'll be good.
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    (Original post by RDKGames)
    Well it shouldn't be. You need to pick g=-9.8 and assume upwards as the +ve direction and you'll be good.
    Okay, thank you!
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    (Original post by allegrosquir)
    Okay, thank you!
    I am a bit confused now. Do I use this: 0=3.6^2 -9.8*2*s ?
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    (Original post by allegrosquir)
    I am a bit confused now. Do I use this: 0=3.6^2 -9.8*2*s ?
    Yes.
 
 
 

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