which cells among the outer and inner hair cells of organ of corti transform the vibration into electrical signals ???

Dear student,
Please find below the answer:

Among the outer and inner hair cells of the organ of Corti, it is the inner hair cells of organs of Corti that transform the vibrations in the fluid f cochlea into electrical signals. These signals are then relayed to the auditory brainstem and auditory cortex via the auditory nerve.

The outer hair cells help in amplifying low-level sounds that come in the cochlea. 

Hope this clears your doubt.
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