Question: A constant rectangular cross-section nanocantilever vibrates in out-of-plane bending, driven by a sinusoidal input displacement applied to the anchor point. Find the equivalent viscous damping ratio of the environment when the cantilever has a length of 60 nm, a width of 5 nm, and a thickness of 120 nm. Young's modulus is 150 Gpa and the mass density is 6000 kg/m3 . The experimentally determined bandwidth is 30,000 Hz.