Effects of Electromagnetic Waves

Light:Temperature, Scattering &

Absorption

Essential Standards

• 6.P.3 Understand characteristics of energy transfer and interactions of matter and energy.

Clarifying Objectives

• 6.P .3.2 Explain the effects of electromagnetic waves on various materials to include absorption, scattering, and change in temperature.

Essential Questions

• How does light influence TEMPERATURE of an object?

• How does the sun’s energy arrive as light?

• How does light ABSORB matter?

• How does light SCATTER matter?

Light Waves• Electromagnet waves

transmit/transfer energy in light waves

• Light is Photon ENERGY that travels through WAVES

• These waves are Electromagnetic Waves

• These Electromagnetic Waves create the Electromagnetic Spectrum

Photons• Photons are particles that have a

0 mass

• Electromagnetic waves are carried through the electromagnetic spectrum by photons

• These photons can move through mediums but do not need to

• They can pass through vacuums

Types of Electromagnetic Waves• There are 6 different types of

Electromagnetic Waves① Radio Waves② Microwaves③ Infrared Waves④ Ultra-Violet Waves⑤ X-Ray Waves⑥ Gamma Waves

• All different types of Electromagnetic waves have the differences

Electromagnetic Spectrum

Effects of Wavelengths

• Shorter Wavelength = more Energy

• Shorter Wavelength = more Photons

• Shorter Wavelength = more Intensity

The Sun

• The sun’s wavelength energy comes to the Earth in 3 ways

• These 3 waves come in different wavelengths

White Light is different• http://www.youtube.com/wa

tch?v=gtgBHsSzCPE

• White light is different because it is a MIXTURE of ALL the COLORS OF THE RAINBOW

• White light shines down on every object just different objects reflect different lights and absorb the rest

• http://www.youtube.com/watch?v=JqLmJ-lDHEQ

• Look at the jerseys of the players & other colors this all started as white light

White Light is different

• All white light goes through a natural prism as it enters the earth’s atmosphere and different objects absorb & reflect different colors

• http://www.youtube.com/watch?v=YWYrjqfZqA8

• Basketball absorbs all light except it reflects orange light (which is what we see)

Essential Questions

• Get with a partner and answer…

• How does the sun’s energy arrive as light?

Electromagnetic Waves (Light) Affect ABSORPTION

• Absorption is the opposite of reflection

• If light is not absorbed it is reflected

• Absorption is how many of the photons of light are going into a material

• The darker a material is the more absorption will take place

Electromagnetic Waves (Light) Affect SCATTERING

• Scattering of Electromagnetic waves is when light hits particles and scatters everywhere

• Light as it is coming down is white as we know when it hits something it scatters

Essential Questions

• Get with a partner and answer…

• How does light ABSORB matter?

• How does light SCATTER matter?

Electromagnetic Waves (Light) Affect TEMPERATURE

• Electromagnetic Waves affect Temperature in three ways

• Temperature will change depending on…① Intensity② Duration③ Absorption (Amount of

Light)

Electromagnetic Waves (Light) Affect TEMPERATURE [Intensity]

• Intensity of light is the #number of PHOTONS being emitted by a light source

• The more INTENSE (photons) the light is the hotter the temperature will be

Electromagnetic Waves (Light) Affect TEMPERATURE [Absorption]

• Absorption is the opposite of reflection

• Absorption is how many of the photons of light are going into a material

• The darker a material is the more absorption will take place

• http://www.youtube.com/watch?v=gtgBHsSzCPE

• 3:40-4:04

Electromagnetic Waves (Light) Affect TEMPERATURE [Duration]

• Duration is the AMOUNT OF TIME that the light wave (photons) is shining on the object

• For example in the summer time the DURATION or time of light is more

• In the winter time the DURATION of light is shorter

• The longer the DURATION the higher the temperature will be

Essential Questions

• Get with a partner and answer…

• How does light influence TEMPERATURE of an object?

EOG Questions• During the day, the sand at the beach is very warm; while at night, it is cooler.

Why does this occur?

• A) The sand reflects the sun’s energy during the day, causing it to become warmer.

• B) The sand absorbs the sun’s energy during the day, causing it to become warmer.

• C) The sand scatters the sun’s energy during the day, causing it to become warmer.

• D) The sand refracts the sun’s energy during the day, causing it to become warmer.

Important Points• Electromagnetic Waves are

either Reflected or Absorbed

• Absorption is how many photons from waves are transfer into a material

• Temperature depends on – Duration of light– Absorption of light waves– Intensity of light waves

• Scattering is when light waves no longer travel in a straight line & start reflecting every which way

• The sun transmits energy through– Infrared– Visible – Ultra violet

• White light carries all the colors of the rainbow and is always scattered