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Gravitational Fields Question AQA PHYSICS A LEVEL Watch

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    Hi, i need help with the following question:

    'Two stars of mass M and 4M are at a distance d between their centres. The resultant gravitational field strength is zero along the line between their centres at a distance y from the centre of mass M. What is the value of the ratio y/d?

    A: 1/2
    B: 1/3
    C: 2/3
    D: 3/4'

    i understand the method behind the answer (finding two equations for g and equating them), however i don't understand why the the common point used for the equations of g is d-y away from the 4M star, i thought it would be d+y ?
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    ???????????
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    (Original post by ithinkitslily)
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    Hi! I'm sorry you've not had any replies, I'll move your thread over to the Physics forum so you can hopefully get more responses. For future reference, here's the subject forum directory
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    (Original post by ithinkitslily)
    ???????????
    https://www.thestudentroom.co.uk/sho....php?t=2708597
    this should help you
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    As for your question about d and y, I hope this image helps...

    Name:  IMG_20171005_184500.jpg
Views: 17
Size:  498.4 KB
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    (Original post by jkedwards)
    As for your question about d and y, I hope this image helps...

    Name:  IMG_20171005_184500.jpg
Views: 17
Size:  498.4 KB
    omfg this whole time i interpreted the y to be a vertical distance :facepalm:i'm actually an idiot lol
    thank you !
 
 
 
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