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    Car travels round banked, circular track. Diagram states:

    R cos theta = mg (Bostock & Chandler Applied Maths Vol 1, p. 277)

    This makes R greater than mg. The diagram in question includes no centrifugal force increasing the pressure of the car on the track, and R is only equal to mg on a horizontal surface.

    Can any one explain how a component can be greater than the force whose component it is?

    I must finally be getting senile.
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    (Original post by graham fyfe)
    ...
    Hint:

    If the car is not moving, then what's stopping it from slipping sideways on the banked track?

    Edit: I've not got the book or seen the picture, so this is partly guess work based on your description.
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    Many thanks for answering so quickly. It's a standard block-on-slope
    situation except that the centripetal acceleration is horizontal, so that whereas the reaction force R (often called N) is usually mg cos theta, things are now the other way round with mg = R cos theta, making the reactive force larger than mg, which doesn't seem to make sense.
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    (Original post by graham fyfe)
    Many thanks for answering so quickly. It's a standard block-on-slope
    situation except that the centripetal acceleration is horizontal, so that whereas the reaction force R (often called N) is usually mg cos theta, things are now the other way round with mg = R cos theta, making the reactive force larger than mg, which doesn't seem to make sense.
    Sarcasm at its best
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    (Original post by graham fyfe)
    Many thanks for answering so quickly. It's a standard block-on-slope
    situation except that the centripetal acceleration is horizontal, so that whereas the reaction force R (often called N) is usually mg cos theta, things are now the other way round with mg = R cos theta, making the reactive force larger than mg, which doesn't seem to make sense.
    Can you scan/photograph the page and supporting text. In low res. if possible - some of the pictures on here are over 3Meg! Any comments I make will otherwise just be guesswork.

    I had the impression that the object was stationary from your first posting, though that no longer looks to be the case from this latter post.
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    Thanks again, Ghostwalker. I (will try to) append a copy of the relevant page with my understanding (?) of it writ large at the bottom. G. Fyfe

    I bet it doesn't work. There's nothing to tell you how.
 
 
 
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