In the presence of an impulse force, such as the forces used to move the actuator during seek operations, {HEAD ~ a large surface} acts like {TAIL ~ a drum} or stereo speaker 
In the presence of an impulse force , such as the forces used to move the actuator during seek operations , { HEAD ~ a large surface } acts like { TAIL ~ a drum } or stereo speaker
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH