



to tin- plane, I- '.10. 



cally, e = i7r-a, and P= IT. 



;. r i'h.- rixth Mechanical - Thi* 



is a triangular prism, and is used to separate obst.u 1 

 introducing its edge between them and then thrusting the 



o forward. This is effected by the blow of a hanm. 



-. which produces a violent pivs.~ 

 short time, sufficient to overcome the greatest forces. 



5. An isosceles wedg< 'n 



on its three faces; to find the relation between them. 



ly ^w 



The above three figures represent the wedge and obstacles 

 together and separately. 



Let 2P denote the force acting perpendicularly to the t 

 end of the wedge; R and I? the forces which act on the - 

 faces of the wedge : these forces are perpendicular to the faces 

 since the wedge is supposed smooth. 



Let 2a be the vertical angle of the wedge. 



Resolve the forces which act on the wedge in < 



ndicular and parallel to the thick end; then for the 

 equilibrium of the wedge we h, 



2P= (R 4- R') sin a, 



7i cos a = R' cos a ; 



therefore 



R = R', 



