342
NANOMACHINES AND NANODEVICES
X
5
Figure 13.7. Damped harmonic oscillator showing (a) dependence of the displacement of a
free-running (no driving force) oscillator on time, and (b) dependence of the amplitude of a driven
oscillator versus the ratio of the driving frequency W' to the undamped natural frequency w for
different damping constants b, where Fo is the amplitude of the driving force. (Adapted from
D. Halliday and R. Resnick, Physics, John Wiley & Sons, Inc., New York, 1960, Vol. 1, p. 31 1 .)
source of damping will be air resistance, which is proportional to the area of the
beam. For the case of a nanosized beam, this area is very small, so the damping
factor b is small. Nanosized beams dissipate very little energy over their vibrational
cycles.
NANOMACHINES AND NANODEVICES
X
5
Figure 13.7. Damped harmonic oscillator showing (a) dependence of the displacement of a
free-running (no driving force) oscillator on time, and (b) dependence of the amplitude of a driven
oscillator versus the ratio of the driving frequency W' to the undamped natural frequency w for
different damping constants b, where Fo is the amplitude of the driving force. (Adapted from
D. Halliday and R. Resnick, Physics, John Wiley & Sons, Inc., New York, 1960, Vol. 1, p. 31 1 .)
source of damping will be air resistance, which is proportional to the area of the
beam. For the case of a nanosized beam, this area is very small, so the damping
factor b is small. Nanosized beams dissipate very little energy over their vibrational
cycles.