WavesTsunami info from NOAA http://www.pmel.noaa.gov/tsunami/indo_1204.html

http://www.youtube.com/watch?v=BvbBgh9ux6A Japan 2011Homework

http://www.atmosedu.com/202Physics/wavesearthactivity.html

Systems with a stable equilibrium point often exhibit Oscillations

B is a stable equilibrium point because1)When the ball is pushed to the right from B the force of gravity acts to pull it back to B2)And when the ball is pushed to the left from B the force of gravity acts to pull it back to B

The Period of an Oscillating system is the time it takes to complete one full cycle

The period is the time it takes to go from A over to C and back to A.

The frequency of an Oscillating system is the number of cycle per second and is just

1/Period

Period

1frequency

The frequency unit of cycles per sec (1/s) has the special name Hertz (Hz)

The frequency of an Oscillating system is the number of cycle per second Period

1frequency

The frequency unit of cycles per sec (1/s) has the special name Hertz (Hz)

What is the frequency of vibration for a humming bird’s wings that has a period of 0.02 second?

The frequency of an Oscillating system is the number of cycle per second

Hz 50s .02

1

Period

1frequency

The frequency unit of cycles per sec (1/s) has the special name Hertz (Hz)

What is the frequency of vibration for a humming bird’s wings that has a period of 0.02 second?

Since the frequency of an Oscillating system is the number of cycle per second, the period

(number of seconds per cycle) is:

frequency

1Period

A seismic signal has a frequency of 0.2 Hz. What is the period of this signal?

Since the frequency of an Oscillating system is the number of cycle per second, the period

(number of seconds per cycle) is:

s 0.5Hz .2

1

frequency

1Period

A seismic signal has a frequency of 0.2 Hz. What is the period of this signal?

Period

Period

λf v

frequenc wavelengthspeed

period

1frequency

T

λ

period

wavelengthspeed

y

Longitudinal wave (like sound, or P-waves through Earth)

Transverse waves (like water waves, light, S-waves through Earth)

Constructive interferance Destructive Interferance

Standing Waves (Interferance pattern that results when a wave traveling to the right interfers with an identical wave traveling to the left.