SAMPLE QUESTIONS ---------------- 1. Which one of the statements about the speed of light is INCORRECT? (a) light travels infinitely fast in vacuum (b) the speed of light is the same as the speed of propagation of electro-magnetic radiation (c) the speed of light in vacuum is the same for yellow and blue light (d) the speed of light changes if it enters a dense medium, like glass (e) the speed of light is different from the speed of sound 2. To produce an absorption line, electrons in atoms must (a) drop down in energy level (b) stay in the same energy level (c) go up in energy level (d) escape the atom completely (e) jump between atoms 3. The force of gravity between two objects (a) depends on the universal constant G (b) increases if the objects are rotating about a common center of mass (c) decreases by a factor of 4 if the distance between the two objects is increased by a factor of 4 (d) depends only on the mass of the more massive object (e) disappears completely when the objects are very far from each other 4. Which one of the following is true? (a) there are several notable examples where angular momentum is not conserved (b) center of mass of the Solar System is at the center of the Sun (c) electro-magnetic radiation propagates as a longitudinal wave (d) electrons in atoms can have any amount of energy (e) energy is not lost or created, only transformed from one form to another SHORT ANSWER: 5. Explain using a sketch and a couple of sentences why Neptune does not show a crescent phase as seen from Earth. MIDTERM I TOPICS ---------------- Seasons, day/night Phases of the Moon Ecliptic Solar and Lunar eclipses Equinox, solstice Sidereal and solar day Heliocentric & geocentric models of the Solar System Retrograde motion of planets Parallax: can measure distance Brahe, Kepler, Newton; Kepler's laws and Newton's laws Linear and angular momentum Newton's law of gravity Conservation Laws: linear, angular momentum, and energy Center of Mass, weightlessness, escape velocity Ocean tides EM radiation: speed of light, wavelength, frequency Transverse vs. longitudinal waves Structure of Atoms, protons, neutrons, electrons Emission and absorption lines - discrete line spectrum Thermal, or blackbody radiation - continuum spectrum Doppler effect (Diffraction) Telescopes: light gathering power, resolution, magnification Formation of the Solar System: collapse from proto-solar cloud/nebula, frost line inner vs. outer planets Radiometric dating