Chapter32 Relativity lp 2l △t 12°x v△t 6 6 C 2 Combine this with the formula △t=12 △t We find: At v/Cc l t 2   x y o s d 12 3 6 9 12 3 6 9 1 x 2 x 12 3 6 9 2 2) 2 ( 2 v t d c    Combine this with the formula t' t' t' 2d c 2 1     We find: 2 ' 1 (v / c) t t   