1. ______________ objects (including metal, air in a container, glass, string under tension, wood, etc) “bounce back” when _______________ , _______________
or ________________ .
They vibrate at a special set of __________________ determined by their:
-size: _________ object  ___________ f
-material: __________material  ____________ f
-shape
-condition
Elastic
compressed
stretched
twisted.
frequencies
larger
lower
higher
stiffer
An object’s _____________ frequency is the one that
requires the _____________ energy to begin and continue.
It also results in the _________________________ vibrations.
natural
least
largest amplitude

2. Ex: What determines the natural frequency of
a simple pendulum?
Its length, l
______________________
_____________________  ____________ frequency
longer length
lower
Ex: What determines the natural frequency of
a mass on a spring?
1. _____________________________
stiffer ____________  _____________ frequency
the spring constant, k
spring
higher
2. _____________________________
more _____________  _____________ frequency
the mass, m
mass
lower

3. _______________ occurs when an object is __________
______________ at its ______________ frequency.
forced
Resonance
to vibrate
natural
During resonance, the ________________ (NOT the ______________ ) of vibration is ______________.
amplitude
frequency
a maximum
Resonating things include:
_______________________
swings
wine glasses
musical instruments
metal bars
bridges
buildings
nuclei (MRIs)
skulls
radio circuits

4. Magnetic Resonance
Imaging

5. Got glass?

7. __________________ forces applied at the system's
________________frequency can lead to ________________ .
Even small
natural
resonance A t
Is the frequency changing?
How can you tell?
No.
The period is constant.