Why does tension decrease along a rotating rod pivoted at one end?

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siddharth23
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I read that if a bar is pivoted at one end and is rotating in a horizontal plane, the tension at a specific point decreases as you go away from the pivoted end.

Only inference I could draw from this is that the centrifugal force, which is the cause of tension, increses as you go towards the free end. But as the rod is a rigid body, tension at a certain point also acts on all points preceding it and the point closest to the pivot has the highest tension.

Is that correct?
 
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hi siddharth23! :smile:

yes, the tension is greatest near the centre …

the tension at r has to supply the force to keep the whole rod from r to R,

so it's bound to be greater as r gets smaller

(alternatively , if you look at just the bit between r and r + dr, the tension at r has to supply the centripetal acceleration, ω2r, after you've subtracted the tension at r + dr !)
 
Thanks a lot Tim..! :)
Gottit!