8th Grade Science 09/24/2014 Essential Question - How does a wave

transfer energy? Objectives - I can...

Describe the relationship between the frequency and wavelength of a wave

Explain why waves travel at different speeds.

Bell Ringer - Copy and answer the following question on your bell ringer sheet.

How are mechanical waves and electromagnetic waves different? How are they alike?

Frequency, Amplitude, and Wavelength8TH GRADE SCIENCE

Waves Review

A wave is a traveling disturbance that carries energy from one place to another.

Energy is the ability to do work or cause a change

Amplitude Amplitude - is

measured from the equilibrium position to the top of a crest or the bottom of a trough.

The amplitude of a transverse wave is a measure of how high the crests are or how deep the troughs are.

Wavelength Another way to describe a wave

is by its wavelength. The highest points of waves

are called crests. The lowest points of waves are

called troughs. A wavelength, for a

transverse wave, is the distance from one crest to the next.

A wavelength, for a compressional wave, is the distance between the center of one compression and the center of the next compression.

The Electromagnetic Spectrum:

Wavelength Visible light is only a small

part of the electromagnetic spectrum.

It is the wavelength of visible light waves that determines their color.

For example – The wavelength of red

light waves is longer than the wavelength of green light waves.

Frequency Frequency is number

of complete wavelengths in a given point.

As a wave length increases in size, its frequency and energy decrease.

8th Grade Science 09/24/2014 Essential Question - How does a wave transfer

energy? Objectives - I can...

Describe the relationship between the frequency and wavelength of a wave

Explain why waves travel at different speeds. Bell Ringer - Copy and answer the following

question on your bell ringer sheet. How does increasing energy affect the

frequency and wave length of a wave?(hint – Think about the turtle and Rabbit picture)

Frequency and Energy As a wave length

increases in size, its frequency and energy decrease.

As a wavelength decreases in size, its frequency and energy increase.

Agenda

1. Review wavelength, amplitude, and frequency.

2. Notes on speed of waves

3. Begin Wave worksheet

4. Correct quizzes and complete reflection sheet

Review Amplitude – the

measurement from the top of the crest, or bottom of the trough, to the middle (equilibrium)

Wavelength – The length of a single wave cycle

Frequency – the number of waves that pass a given point in a given amount of time.

Speed of Waves To calculate the speed of the wave, use the

formula:

Wave speed = Wavelength X frequency

10 cm

10 cm

Calculate the speed of the wave

5 cm

a. Wavelength _______ b. Amplitude _________ c. Frequency _______ d. Speed_________