490 O. Grin 
0.6 
0.4 
yv:2 
2 
Fig. 3. Heaving motion; plot of force R for B= 0.7 
C represents the hydrodynamic mass in nondimensional form, i.e., 
m 
Tp? (17) 
8 B 
A represents the ratio of the amplitudes, i.e., the ratio of the amplitude of the surface 
waves drifting away from the body to the amplitude of the heaving motion. Between A 
and R; the relation 
R, = pee aie 
w*B 
(18) 
holds because the work done by the force in unit time equals the energy dissipated by 
the waves. 
For cases (b) and (c), viz, the restrained body in transverse or longitudinal waves, respec- 
tively, the following results are represented: 
