A heavy F iose length is -a rests on 



cumference of a rough vertical circle of radius a; if the Mrm- 

 be in a position of limiting r<iuililrium. and it' ft !>< the. 



listance of its highest . \tnmity from the vn; 

 ircle, shew that 



and explain this result when (1 ft*) e* 2/i is nega: 



Also if p be such that = 0, shew that the whole, pressure 

 on the curve is to the weight of the string as 2 is to 



