46 OUTLINES OF NATURAL PHILOSOPHY. 



be called g, if after any time t, its velocity be v r 

 v~gt\ and if s be the space through which it has 

 descended, % s =s= ft 2 , or v = 



a. Since v=:gt, and therefore t^m 



2s 



b. Hence if t = 1", and if s' be the space fallen through 

 in one second, g = 2 s' ; or the velocity is equal to 

 twice the space fallen through in one second. 



The space through which a body falls in the first se- 

 cond of time is sixteen feet and one inch nearly, 

 and therefore g 32 J nearly, 



89. If the velocity acquired by a body falling 

 from rest, were at the end of any time to become 

 uniform, the body, in an equal time, would move 

 over twice the distance which it has actually fallen 

 through. 



90. If a body be projected directly upwards 

 with any velocity c, its motion will be uniformly 

 retarded, or it will lose in every second a velocity 

 equal to g, the velocity generated by gravity in a 

 second. 



After the time t, the velocity of the body is c tg; 

 and the time at which the body reaches its greatest 



height where ^ = 0, is -. 



91. The 



