Unit 7: Light and Matter- The Sun Flashcards
Why does a heated Iron poker glow?
- Emits photons of visible light
- As the object heats up, it gets brighter, emitting more photons of all colors (wavelengths). Brightness (intensity of radiation) is the #of photons emitted per second increases
What is the color of the brightest/ most intense wavelength?
Shifts towards the violet end of the spectrum as the temperature increases.
What is Blackbody Radiation?
A theoretical or model body which absorbs all radiation falling on it, reflecting or transmitting none
- A blackbody absorbs and emits entire spectrum of electromagnetic radiation.
Do photons with a shorter wavelength carry more or less energy than a photon with a linger wavelength?
More
- red, orange, yellow, green, blue, violet (least to most energy)
How are elements arranged on the Periodic Table of Elements?
They are arranged in order of increasing number of protons (atomic number)
How are the elements in each column related?
They have similar chemical properties
What are spectral lines and when do they occur?
- When an electron jumps from one energy level (or ‘Orbit’) to another
(Absorption and Emission)
What is a Spectroscope used for?
To examine the wavelengths of light emitted from a source
What are the steps of a spectroscope?
- Add a chemical substance to a flame
- send light from the flame through a narrow slit then through lenses and a prism
- Bright lines in the spectrum show the the substance emits light at specific wavelengths only
What is the Absorption Spectrum for Hydrogen Gas?
The line appears as dips in the intensity vs wavelength graph
What is the Emission Spectrum for Hydrogen Gas?
flat intensity at 0
with spikes in intensity as wavelengths increase
What are the Two kinds of Glowing Gas Clouds?
Hydrogen and Oxygen rich clouds
What color are Hydrogen Rich Glowing clouds?
These clouds glow red
What color are Oxygen Rich Glowing clouds?
These clouds glow green
What is the Doppler Effect?
The wavelength of light is slightly shifted when the source is traveling toward or away from the observer
What are the two types of shifts seen in the Doppler Effect?
Red and blue shifts
What Is a red shift?
When stars are moving away from us, The spectral lines are shifted to red
What is a blue shift?
When stars are moving toward us, the spectral lines shifted to blue