OP FORCES IN OMB PUUIB, 1 



weight of u I ; shew that the nBfrMfrm of the 



horizon-tan" 1 ^" 'tanaj; a, 6 being thr 

 of the centre of gra beam from its ends, and 



M, 



two 



that 



mM 



square is placed with its plane vertical between 

 he same horizontal line; anew 

 it will bo in equilibrium when the 



< edges to the horizon - ) sin" 1 c , fa being the 



length of a side of the square, and c the distance between 

 the pegs. Shew that tho * not be affected by 



the application of any force which binccts the straight line 

 joining the pegs and passes through the lowest point of the 

 square. 



One end of a tri: <1 to the extremity of a 



smooth uniform r-l. a:, i r to a ring without * fight 



i passes over the rod, and the 

 smooth peg. Determine the least length of the string tor 



v that th 

 the roil to tho vertical cannot be less than t 



ng has one end attached to the 

 of a smooth uniform heavy rod two i 



irries a ring without weight which slides 

 10 rod. Tho rod is suspended by means of the string 

 a smooth peg; shew that if 6 be the angle which the 

 rod makes with the horizon, then 



\ square rests with its plane perpendicular to a 



smooth wall, one corner being attached to a i the wall 



by a string whose length is equal to a side of the square ; 



that the !i tancca of three of its angular points from the 



wall are as 1, 3, and 4. 



L.M. < f a beam, whose weight is If, u placed 



-mooth horizontal plane ; the oi . a string 



r smooth plane inclined at an 

 angle a to tho horizon ; the string passing over a pally at 



