1. EMS review

2. 1.Look at the above H-R diagram and list the sequence of stars from greatest to least luminosity. Deneb, Spica, Capella, Sirius B 2.Which star is the youngest? Spica 3. How is temperature related to this diagram? Hottest on left coolest on the right.

3. 4.Explain the life cycle of a star. Feel free to draw a diagram. Nebula (protostar), main sequence giant, white dwarf Supergiant neutron star black hole 5. What is a light year? What is its relationship to distance? How are they both related to an Astronomical Unit? The distance light travels in a year. The light year is much longer than the Astronomical unit.

4. 6. What is the difference between absolute and apparent magnitude? Absolute magnitude is actual brightness. Apparent magnitude is how bright it appears from earth. 7. Explain how you can use spectral data to find out which elements are in the light that stars emit. Think of your Star Spectra Gizmo and Lab. Compare the spectral data from a star to the data of elements we know. If they match the element is in that star.

5. 8.What is the difference between red shift and blue shift? How is the Doppler Effect related? When an object moves toward us the light waves bunch up and appear more blue. When an object moves away from us the light waves spread out and appear more red. This changing of frequency because of motion is the Doppler effect.

6. 9.How are frequency, wavelength, and energy related? Higher frequency is a shorter wavelength and higher energy. Lower frequency is a longer wavelength and lower energy. 10. How is radiation related to EM waves? EM waves are forms of radiation

7. 11. What is the difference between ionizing and non-ionizing radiation? Non-ionizing is lower energy and safe (radio, microwave, infrared, and visible light). Ionizing is high energy and dangerous (UV, X-ray, and Gamma rays). 12. What do the numbers on the spectrum indicate? Wavelength in meters or frequency in hertz (Hz).

8. 13. If Vega is 32 light years away, when we see the light from Vega today, what year was it actually emitted? 2015-32=1983 14.What does Edwin Hubble have to do with red shift / blue shift? Edwin Hubble used the red shift/ blue shift (Doppler effect) to measure the distances to galaxies and found evidence the universe is expanding which supports the big bang theory.

9. Also study your EMS notes and your properties of waves(light) notes.