Equation 7-76 can now be used to find Tp^. 



Hj, d^ 

 p = 101 w (D + d,), 



P^ = 101(64) — ^ — -^ — (11.96 + 7.5) , 

 »« ^ 109.6 11.96 



= 6,050 Ibs./ft. (T = 6 sec.) 



A similar analysis for the 10-second wave gives, 



p = 3,300 Ibs./ft? (T = 10 sec.) 



The above values can be obtained more rapidly by using Figure 7-75, 

 a graphical representation of the above procedure. To use the 

 figure, calculate for the 6-second wave, 



^s 7.5 



= 0.0065. 



gT^ 32.2 (6)2 



Enter Figure 7-75 with the calculated value of dg/gT^, using the 

 curve for m = 0.05, and read the value of p^/wH^,. 



= 11.3. 



Using the calculated values of H-,, 



p^ = 11.3 w H^ = 11.3(64) (8.4) = 6,075 Ibs./ft? , (T = 6 sec.) 

 For the 10-second wave, 



p^ = 5.3 w Hj, = 5.3(64) (9.8) = 3,300 Ibs./ft? (T = 10 sec.) 



The force can be evaluated from Equation 7-77 



Pm^b 6,050(8.4) „ , 



R^ = — — = - — -^ = 16,900 Ibs./ft. , (T = 6 sec.) 



and 



R^ = 11,500 Ibs./ft. (T = 10 sec.) 



7-149 



