Jawabanmu

2014-02-02T10:13:23+07:00
Dik : f = 40 Hz         
t = 1 menit = 60 s   
T = 1/f
   = 1/ 40
fase getaran = t/ T                    
= 60 / 1/40                    
= 60 . 40 /1                   
= 2400