True or false: depolarization is unidirectional down an axon because voltage gated na+ channels are inactivated and k+ channels are open in the membrane that was just depolarized, whereas downstream voltage gated na+ channels are receptive to a depolarizing stimulus.

Aturning operation is performed with following conditions: rake angle of 12°, a feed of 0.35 mm/rev, and a depth of cut of 1.1 mm. the work piece is aluminum alloy 6061 with t6 heat treatment (a16061-t6). the resultant chip thickness was measured to be 1.0 mm. estimate the cutting force, fc. use shear stress of 207 mpa and coefficient of friction on the tool face of 0.6.