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Monday Group 1 Group 3 Spring 2010 Lab Final Quiz Review The quiz will be worth 25 points and will be 30 minutes long. There will be a review session 1 hour before the lab starts (7:30pm-8:30pm). You may also come to my office hours or contact me with any questions. The quiz is closed note and closed book, but calculators will be allowed. You should have a scientific, non-programmable calculator. You should know some simple equations that are mentioned in this review, but more complicated equations will be provided. Scientific notation should be used in your answers when appropriate. All work shown and final answers must have proper units to be considered correct. The quiz is not going to test you on every little detail covered in lab. Instead it will be over what we the TA's consider to be important concepts in the labs. The following contains the general ideas of what we consider important. If you have any questions please contact me at ([email protected]). Luminosity, Brightness, and Distance: the Inverse Square Law (Pg. 23) Define the following terms: luminosity and brightness. How are they different? What is the relationship between brightness, luminosity, and distance? If I change one of the quantities how will the others be affected? You need to know the equation: 1 L B = 4π d 2 For a 100W bulb and a 200W bulb know how to measure the luminosity and the brightness. How were we able to calculate the wattage of the two unknown bulbs? Know how to solve for different terms in the brightness equation and how to use the equation when you are comparing two different light sources. Starry Night Introduction (pg. 127) Know the definition of circumpolar and how your location on earth effects circumpolar constellations. Know what constellations are circumpolar in Lafayette. Know the definition of zenith and how your location on earth affects your zenith. Know how your position on Earth affects the relative position of Polaris and the correlation between Polaris’ height in degrees above the horizon and your latitude on the northern hemisphere 1 Know how the rotation of the earth affects the rising, setting and rotation of all constellations/stars. Telescope Know the difference between magnification and angular resolution. Know which is important and why. M=f obj /f eye Know how to make the angular resolution better and how to make the magnification better. Given two lenses, how far apart do they need to be in order to be in focus? Why do images flip when viewed through 2D lenses? 3D lenses? Know how to build a telescope given the necessary components. Starry Night: Observing the Stars What are sunspots? How do we see them? How do we use sunspots to measure the rotation of the sun? How does the sun change with seasons? Why do we have seasons? Know what an Analemma is and what shape it is in. How will the constellations change in 5,000 years? Why will they change? Distance to the Stars What is the definition of parallax? Be able to draw a diagram indicating the angles involved. How does distance affect the parallax angle? When is parallax a useful technique? Practice unit conversions and calculations involving rate, distance traveled and time. Know the appropriate equations. α = 1/L Know how to do basic trigonometry of right triangles. Given an angle and a length of one of the sides, can you determine one of the other sides of the triangle? 2 Given a velocity and a distance, know how to calculate a time in various units. v=d/t Why can't you use parallax to measure the distance to planets? Stars, Light and Spectra (pg. 3) Why do scientists use spectrum measurements? What are some devices used to measure spectra? Where can we see spectra in our lives? What are the three basic types of spectra? You should be able to describe each type and provide an example. Also, what examples were used in lab to show the three types of spectra? How do filters work? What will you see if you combine filters together? What do the filters used in the lab represent in astronomy? What is the relationship between wavelength and frequency? How does the energy of a photon relate to wavelength and frequency? Be able to describe what is happening at the atomic level to create an emission spectrum or an absorption spectrum. (Think of the slide and little girl example I used) Are all energies of the electron shells allowed? 3D lab Know what the local group is. Know what kind of galaxy the Milky Way is. Know the three main types of galaxies Be able to describe the 3d shape of the Milky Way. Hubble Where is the center of the universe? How do we measure the Doppler shift from distant stars or galaxies? What is a Doppler shift? ˰ What does a redshift mean? What does a blueshift mean? What does this mean about the velocity of the object? 3 Do closer galaxies move faster than galaxies further away? What happens when the Hubble constant changes to 0 km/s/Mpc? What about infinity km/s/Mpc? Given the Hubble constant, how can we calculate the age of the universe? ͪ Ͱ Constellations/Asterisms (back of lab manual) Know how to find and draw the following constellations and major features. Also, review some myths you found interesting. Big Dipper , Dubhe, Merak, and Mizar Little Dipper , Polaris Cassiopeia , Schedir Canis Major/Minor, Sirius, Procyon, M41 Orion , Betelgeuse, Rigel, M42 (Orion’s Nebula) Gemini, Leo, Regulus Taurus , Aldebaran Auriga, Capella Winter Hexagon (Sirius, Rigel, Aldebaran, Capella, Castor, Procyon) Cepheus Note: There is a separate review for the constellations on the web (it may contain more constellations that your lab has covered). 4 .
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