78 Lecture 4 
RESPONSE RATIO, R (db) 
-100 
FREQUENCY (CPS) 
Pig: an wees ratio of the system of Fig. 4.8 with masses m added at the beam center. M=10M,, 
fine 1 [10]. 
mount and the mass m are inserted together. Since the ratio of force applied 
to the end supports of the beam to the amplitude or force at its center is the 
same with or without the spring and mass present, the response ratio is also 
the ratio of support forces after and before the spring and mass are inserted. 
