EXAMPLES. 



11. li square table v. 



11 11 at distances . -in tin- < . 1 t. it an- 



th pullies at tl. 

 ii] 'porting weight* P,, P f , 1\. 

 equilii'riuin, 



P 7' /' P\ f r f /P /'N 1 /P P\* 



j + j + ' + *) L.f5+5) + ('. + M 

 <\ <*. r . >* r '' ^ 



Shew also that 



Two Pmall rinirs slide on the arc of a smooth vertical 

 : a strin.-: ]>asscs through btli rin.irs. and lias three e<jiial 



weights attaeln-d to it, one at raeii end and one let\veen the 

 ; iind tlie position of the rinirs when tliev are in 



librium. The rings are supposed without weight 



K..eh of the rings must be 30 distant from the 

 highest point of the circle. 



. The extremities of a string without weight are fast 

 to two equal heavy rinjrs which slide on smooth fixed rods in 

 vertical plane and equally inclined to the vertical: 

 and to the middle point of the strinir :i weight is 

 equal to twice the weight of each rin;_r; iind the }> 

 equilibrium and the tension of the string. 



If the point to which the weight is fastened bo not the 

 middle point of the string, shew that in the portion of equi- 

 librium the tensions of portions will be equal. 



11. A light cord with one end attached to a fixed point 

 passes over a pully in the same hori/ontal line with the : 

 point and supports a weight h :n -ely at its other 



A h< to the cord in different ]> 



between t point and the pully, it is required to iind 



the locus of its positions of equilibrium. If the weight of the 

 ring be small compared with the other weight, the locus will 

 be approximately a parabola. 



