Harvard Psychological Studies, Volume 1 / Containing Sixteen Experimental Investigations from the Harvard Psychological Laboratory.

by Unknown

t =	W + p ,
	r

and

t =	s - W ,
	r'

r'(W + p) = r(s - W) ,

W(r' + r) = rs - pr' ,

W =	rs - pr' .(2)
	r' + r

Now when pendulum and disc move in the same direction,

W =	rs - pr' ,	(1)
	r' - r

so that to include both cases we may say that

W =	rs - pr' .(3)
	r' ± r