Nitro-. a combining form or an adjective denoting the presence of niter. Nitro-. a combining form (used also adjectively) designating certain compounds of nitrogen or of its acids, as nitrohydrochloric, nitrocalcite; also, designating the group or radical NO2, or its compounds, as nitrobenzene.
The commonly stated range of human hearing is 20 Hz to 20 kHz. Under ideal laboratory conditions, humans can hear sound as low as 12 Hz and as high as 28 kHz, though the threshold increases sharply at 15 kHz in adults, corresponding to the last auditory channel of the cochlea.
How is pitch or frequency determined? Range of hearing: 20-20,000 Hz. Range in volume 10 6! Sound processing is very complex and involves positive feedback. Feedback enhances sensitivity, but can go above one and ear starts vibrating by itself. The ear actually produces a tone â this is the ringing in your ear. 1  Basilar membrane resonates when a sounds wave enters: Different parts resonate at different frequencies. 2  Resonant frequencies are spaced logarithmically â like a piano. 3  A single input frequency can activate a range of nerves on the Basilar membrane: