1. How do you describe a wave?
I. Properties of a Wave
A. Amplitude
1. Height of a wave from the midline
2. Greater amplitude Greater Energy

2. Bright Bulb = High Amplitude
Dim Bulb = Low Amplitude
Bright Bulb = High Amplitude

3. Quiet = Low Amplitude
Loud = High Amplitude

4. Little Waves
Big Waves
Small Amplitude
Large Amplitude
Little Energy
Great Energy

5. a. ex. crest to crest, trough to trough 2. Also called one “cycle”
B. Wavelength (λ)
1. Distance between two equal points of a wave
a. ex. crest to crest, trough to trough
2. Also called one “cycle”
C. Period (T)
1. The time it takes to complete one cycle A A B B
a. Usually measured in seconds

6. D. Frequency (ƒ) 1. The number of waves that occur each second
a. “cycles per second”
b. Measured in a unit called Hertz (Hz)
2. Faster vibration higher frequency
3. Frequency and Period are “inverse”
frequency = period
b. period = frequency

7. What is an “Inverse Proportion?”
Frequency
Period
Period
Frequency

8. Todays Lab: Frequency & Period
Problem 1: Find the frequency of a pendulum for FIVE different lengths and graph it.
Problem 2: Using the same data you just collected, graph the period of the wave vs length.
Problem 3: Explain, in one sentence each, what the graphs mean.

9. # of Swings in 10-sec. Frequency (Hz) Period of the wave (s)
Length (cm)
# of Swings in 10-sec.
Frequency (Hz)
Period of the wave (s)
Average
Average
Average
Average
Average

10. What you will be graphing...
Graph #1: Length vs Frequency
Frequency (Hz)
Length (cm)
Graph #2: Length vs Period
Period (s)
Length (cm)