P2207_fall10_lecture20 - animal speed up and slow down,...

Info iconThis preview shows pages 1–22. Sign up to view the full content.

View Full Document Right Arrow Icon
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Today: Damped Oscillations ( not damned oscillations…) Driven Oscillations Twist angel of spider suspended from its silk thread strong damping (that’s why they hardly ever twist!)
Background image of page 2
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 4
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 6
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 8
The mechanical energy of a damped harmonic oscillator decays by a factor of 4 in 10 s . How long does it take to decay by a factor of 16 ? A. 10 s B. 20 s C. 40 s D. 80 s E. 160 s
Background image of page 9

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Harmonic Oscillator: m k 0 T=2 / o
Background image of page 10
m k m b m k 2 2 4 b m time decay Energy Damped Harmonic Oscillator: ) / ( ) ( m bt m e x t x 2 Damping force: bv F
Background image of page 11

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 12
Background image of page 13

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 14
Resonance and Driven Oscillations in Animal Movement
Background image of page 15

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Problem: Nature didn’t invent the wheel • Animal motion requires that parts of the
Background image of page 16
Background image of page 17

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 18
Background image of page 19

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 20
Background image of page 21

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Background image of page 22
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: animal speed up and slow down, with a corresponding variation in kinetic energy. Doing this with muscles alone would waste too much energy. Solution: Use springs ( tendons, ligaments, muscles ) to convert kinetic energy to and from elastic potential energy . Drive the system near its resonant frequency to get the maximum motion for a given energy input. A Wallaby Hopping: A Human Running: An Insect Flying: A Dog Panting: A Dog Panting: m L 3 , k A/L L T=2 (m/k) 1/2 T L size of dog L...
View Full Document

Page1 / 22

P2207_fall10_lecture20 - animal speed up and slow down,...

This preview shows document pages 1 - 22. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online