Download Chapter 24 sun and light

1. What is the earth’s primary source
of energy?
The Sun
2. What is the sun made of?
Gas
3. Draw the sun and label the four
main parts.
4. Photos
Light
5. Sphere
Ball
6. The photosphere is the surface
of the sun. What does it do?
Radiates light from the sun
7. The sun’s photosphere is composed
of 90%__________
Hydrogen and 10%_________.
Helium
Hydrogen atoms
8. Chromosphere
Thin layer of hot gases
9. Corona
Outermost portion of the
solar atmosphere
10. Solar Wind
Streams of protons and electrons
that boil from the corona
11. Sunspot
Dark areas on the surface of
the photosphere
12. Why do sunspots appear dark?
Because of their cooler temperature,
1500 k (2240.33 °F) less than the
surrounding solar surface.
13. Prominences
Huge cloudlike structures made of
chromospheric gases
14. Solar Flare
Brief outbursts of energy
from a sunspot
Solar Flare
15. What do solar flares release?
Ultraviolet, radio, and X-ray radiation
16. What causes an Aurora?
A strong solar flare
17. What is another name for an Aurora?
Northern and Southern Lights
18. Deep in its interior, the sun
produces energy by a process known
as __________
Nuclear _________.
Fusion
H
H
19. What happens during the process of
nuclear fusion?
• Four hydrogen nuclei are converted
into the nucleus of a helium atom
• Energy is released
20. What is Einstein’s equation and
what does it mean?
• E = mc2
• The energy of an object is equal
to its mass X the speed of light squared
1. Electromagnetic Radiation
Types of energy.
Gamma rays
X-rays
Ultraviolet light
Visible light
Infrared radiation
Microwaves
Radio waves
Longer
wavelength
Shorter
wavelength
2. Wavelength
Distance from one wave crest (top) to the next.
3. Frequency
The number of waves in a certain distance.
4. Electromagnetic Spectrum
Arrangement of waves according to
their wavelength and frequencies.
5. Speed of Light
300,000 km/s or 3.0 x 105 km/s or 3.0E5 km/s.
All forms of energy waves travel at this speed.
How fast is the speed of light in
miles per hour?
1 km per hour = _______________
mph
0.621371192
300,000 km per second X 60 seconds =
18,000,000 km per hour
18,000,000 km per hour X 0.621371192 =
11,184,681.456 mph
6. Visible Light
The band of electromagnetic radiation we can see.
7. Photon
Stream of light particles, a small particle of light.
8. Radiation Pressure
The force exerted by photons.
Photons actually push on matter.
Radiation
The transfer of energy (heat) through
space by electromagnetic waves.
Table 1: Colors and Corresponding Wavelengths
COLOR
WAVELENGTH
Violet
380-440
Blue
440-500
Green
500-560
Yellow
560-590
Orange
590-640
Red
640-750
9. Which color has the longest
wavelength?
RED
10. Which color has the highest
frequency?
VIOLET
Longer wavelength = Lower Frequency
Shorter wavelength = Higher Frequency
More Energy
24.1 The Study of Light
Spectroscopy
 Absorption Spectrum
• An absorption spectrum is a continuous
spectrum produced when white light passes
through a cool gas under low pressure. The gas
absorbs selected wavelengths of light, and the
spectrum looks like it has dark lines
superimposed.
24.1 The Study of Light
Spectroscopy
 Emission Spectrum
• An emission spectrum is a series of bright lines
of particular wavelengths produced by a hot gas
under low pressure.
• When the spectrum of a star is studied, the
spectral lines act as “fingerprints.” These lines
identify the elements present and thus the star’s
chemical composition.
Formation of Spectra
24.1 The Study of Light
The Doppler Effect
 The Doppler effect is the apparent change
in frequency of electromagnetic or sound
waves caused by the relative motions of the
source and the observer.
 In astronomy, the Doppler effect is used to
determine whether a star or other body in
space is moving away from or toward Earth.
The Doppler Effect
Doppler effect on light