'.limit \v. 



r rod 



equal to *jJ//, and attached n' ex- 



rmcr, BO as to turn freely about t! 



force 

 applied at D in order to produce equilibn 



form of the arc of a 



-!IH /' .1- i Q suspended from ita ez- 



resta with ita co: <lown wards on a horizon- 



librium. 



Re* -c the angle which the arc subtends a 



-f tin to the vertical < 



radius at the extremity of which Pis suspended ; t 



tan 



.0 sides of a rhombus A BCD an- hinged tog* 

 at the angles; at A and C are two pulling forces (7 

 diagonal AC; and at B and /> thrrc ar< 

 *rces (Q, Q) acting in BD\ shew that 



7J, DC are two equal and uniform beams < 

 by a hinge nt xed hinge at -rl ; a string fast- 



' ' passes over a pully at D and is attached to a 

 . I n is horizontal and equal to twice the length of 

 shew that if P be such as to keep DC horizontal 

 P . IF. ^}, and tan - 2 tan <f> = 2 V2, where and < arc 

 the angles whirl i .!/.'. C7) make with /.on, and 



lit of each beam. 



string ABCDEP is atto- e A of a 



pully whose radius is r ; it then passes over a fixed point /> 



pully which it touches at the points Cand /> : 



passes over a fixed j> 1 has a weight P 



~ Jr, and 



if the system :u the 



pully is J/', and find the distance AR 



~. 



N 



