Summary

• Oscillatory motion
• Mass on spring
• Energy and oscillations

Bonus question Ch.14


• Written Quiz Ch.14





• The physical pendulum



• Damped oscillations
• differential equations
• damping constant b
• reduced frequency, lengthened period
• exponential decay of energy
Example #1
Example #2





• Resonance
• adding energy
• graphs applet
• radio, microwave ovens, etc.
• Tacoma Narrows Bridge
Example #3 (physical pendulum)

pse6 14.34
A frog in a 6.00-cm radius hemispherical pod barely floats in a pool of ρ = 1350 kg/m³ blue-green ooze. If the pod has negligible mass, what is the mass of the frog?
A. 611 g
B. 323 g
C. 898 g
D. 1.12 kg
Answer



















klm
Which of the following displacement functions x(t) would best correspond to a damped oscillator with a damping constant of b = 0?
A. function A
B. function B
C. function C
D. function D
Answer



















HRW10e 15.59
For the damped oscillator shown, m = 1.50 kg, k = 8.00 N/m, and b = 0.230 kg/s. The block is pulled down 12.0 cm and released. How many oscillations does the block make before its amplitude falls to one-third its initial value?
A. 0.785 oscillations
B. 1.05 oscillations
C. 5.26 oscillations
D. 14.3 oscillations
Answer



















HRW10e 15.47mod
At what frequency f should a uniform solid disk of radius R, pivoting about an axis a distance d = R from its center (at the disk's edge), be driven to maximize the amplitude of its oscillation?


Answer







































answer

A. 611 g




















answer

A. function A
If b = 0 then no damping occurs, and the oscillator amplitude and energy remain constant.



















answer

C. 5.26 oscillations




















answer