2.3 Free Undamped Vibration of the Sdf System
23
Fig. 2.8 Example 2.3
where L AB and L C D are the lengths of the members AB and CD.
Putting the numerical values
k eq =
12 × 30 × 10
12
(1000) 3
+
12 × 30 × 10
12
(800) 3
= 1,063,125 N/mm
Therefore, the natural angular frequency is given by
p =
k eq
m
=
1,063,125 × 9810
30 × 10 6
= 18.645 rad/s
The time period is given by
23
Fig. 2.8 Example 2.3
where L AB and L C D are the lengths of the members AB and CD.
Putting the numerical values
k eq =
12 × 30 × 10
12
(1000) 3
+
12 × 30 × 10
12
(800) 3
= 1,063,125 N/mm
Therefore, the natural angular frequency is given by
p =
k eq
m
=
1,063,125 × 9810
30 × 10 6
= 18.645 rad/s
The time period is given by