 # Chapter 23 Physical Science

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Chapter 23 Physical Science
WAVES Chapter 23 Physical Science

REVIEW OF WAVES

Waves transfer what? ENERGY!!!!

What are the two main types of waves?
MECHANICAL WAVES ELECTROMAGNETIC WAVES

Which type of wave requires a medium?
MECHANICAL WAVES Electromagnetic waves do NOT need a medium.

What are 3 examples of Mechanical Waves?
Water waves Sound waves Seismic waves

What are some examples of Electromagnetic Waves?

Microwaves

Infrared light Visible light Ultraviolet light

X-rays Gamma Rays

What are the colors of Visible Light?
R O Y G B I V

R O Y G B I V RED ORANGE YELLOW GREEN BLUE INDIGO VIOLET

Which color is the HIGHEST energy wave?
VIOLET

Which color is the LOWEST energy wave?
RED

What 3 characteristics do All Waves have?
Amplitude Wavelength Frequency

What does the size of the amplitude of a wave tell us?
HIGH AMPLITUDE = HIGH AMOUNTS OF ENERGY LOW AMPLITUDE = LOW AMOUNTS OF ENERGY

What unit do we use to measure Wavelengths in?
Meters

What greek letter do we use to represent a wavelength?
Lambda 

What are the 3 units we can use for Frequency of a wave?
Waves / second Cycles / second 1/s = Hertz (Hz)

Name the 2 types of Mechanical waves.
TRANSVERSE WAVES LONGITUDINAL WAVES

Which type of wave form crests and troughs?
TRANSVERSE

COMPRESSIONS RAREFACTIONS
Longitudinal wave do not have crests and troughs, instead they have what? COMPRESSIONS RAREFACTIONS

How does the medium move when a longitudinal wave moves through it?
The medium vibrates horizontally.

Surface Waves move both horizontally and vertically simultaneously, which produces what kind of movement? Circular

Speed of Waves What is the wave equation?
V = f  speed = frequency times wavelength

The speed of a wave is held constant within a medium
The speed of a wave is held constant within a medium. So what effect on the wavelength of a wave would you expect if the frequency were doubled? The wavelength would half as much. When frequency goes up the wavelength must go down.

The density of water is 1 g/ml and the density of syrup is 3 g/ml
The density of water is 1 g/ml and the density of syrup is 3 g/ml. Which of the above would you expect a wave to travel the slowest through? A wave would travel the slowest through the SYRUP. Waves travel slower through dense mediums.

A slinky is a very elastic object
A slinky is a very elastic object. Explain why this is used to demonstrate wave motion instead of an object like a tree branch? A slinky has HIGH ELASTICITY ! The higher the elasticity the higher the speed of a wave traveling through it.

Name the 4 ways waves interact.
Reflection Refraction Diffraction Interference

Explain reflection of a wave.
Bouncing back of a wave after it strikes a boundary.

Explain Refraction. The change in path of a wave when it moves into a medium of a different density.

Explain Diffraction. The curving of waves around barriers and ability of waves to spread out in circular pattern after passing through a narrow opening. See picture below.

What are the 2 types of Interference?
Constructive Destructive

Which of the pictures below is an example of Constructive Interference?
The picture on the left is constructive interference. The picture on the right is destructive interference.

Nodes and Antinodes are parts of what kind of wave?
Standing Wave

The frequency at which a standing wave occurs is called what?
Resonant Frequency Sometimes called Natural Frequency.

The End of the Waves Review.