ANSWERS. 



Pages 9, 10. 



(1) 40. 



(2) (0)4* and 5}; (b) - 2$, 6f 



(3) If the original velocities are of the same sense, ^ 

 v 1 = 46^- ; if not, v = 19^, v 1 = lof . 



(4) e = o gives (a) 44^, (b) - 2^ ; <? = i gives (0) = 38^, 

 v' = 49i> () = - 55i> ' = 35f 



(5) = -*. (7) SJft. 

 (8) (a) 0-31 ft; W 9isec.; (,) 66^ ft. 



(n) () 4 ft. per second; (3) 28 ft. per second. 



(12) For^ = o: (a)v = - u\ (f}\\mv Q\ (c)\imv=u r . 

 w -f- m 



1H Wl i 2 W 



- - u, v 1 = 



m -f m' m + 



Hm v 1 = o ; (V) Hm z; = 2 #' ^, lim v' = #'. Interpret these results. 



T-I / \ i / z\ i* 



For ^ = i : (a) v - - u, v 1 = - - u ; (b) hm v = u, 

 m -f m' m + m' 



Page 14. 



(1) About 450 pounds; 9-375 and 0-191 foot-pounds. 



(2) 156-85 foot-poundals. (6) 4^- tons. 



(3) 3 6 3 foot-tons; 9 miles per hour. (7) 13 and 2 foot-tons. 



Page 16. 

 (i) 56-83 F.P.S. units. (2) 16 ft. per second. 



( 3 ) v = 10, /3 = 4 8F, v' = i6i ft' = isF- 



227 



