232 ANSWERS. 



Page 79. 



For. ,, 



= -.I; for n = -2, f(r) = f(V - a 2 ) . r ; for =i and 



I/O 



= ; for n = 2 and = o, f(r) = 



(2) Taking the diameter perpendicular to the force as axis of x> 

 find F- 

 initial velocity. 



we find F- - , where is the radius, <r the ^-component of the 



+ i - n 

 (4) 



(5) Ellipse, parabola, or hyperbola, according as /u, yfy*, where 



j; is the initial distance from the plane, y the initial velocity perpen- 

 dicular to the plane. 



Page 83. 



(2) Let p!, p 2 be the distances of m lt m 2 from the common centroid 

 at any time /; i = Xi x, etc.; then the equations of the relative 

 motion are 



i ^ & </% (m^rm, \ ^ 2 



* ^ ' ; = l7 "~ * ' 



Pages 93, 94. 



(4) (^) 7i pounds; (<5) 735. 6 pounds; (<r) 1 20 ft. per sec. 



(5) 4840 pounds. (9) 32-20 ft. per sec. 



(6) e = 1 inches. (12) 4-7 pounds. 



4 



(7) 8-6. (13) (a) 76permin.; (b) 108. 

 (14) In Fig. 23, CD-.RF = PC\ PR, hence CD = ^-^ = const, 



