Physics of Astronomy week 4, winter 2004 Celestial Mechanics Star Date Review motion of Moon and Mars Starry Night animations Jupiter’s size and distance – workshops Gravity review: Physics Ch.3-6 Figures for Astrophysics Ch.2 Learning plan

Use Kepler’s 3d law to weigh Jupiterweigh Jupiter

Ch.3: Kinematics in 2D: Vectors Review vectors. Add component by component. Forces in the y direction do not affect motion in the x direction Uniform circular motion: Galilean relativity: Motion of an object depends on the motion of its reference frame Gravity review: Physics Ch.3-6

 Force = mass * acceleration, where a = dv/dt N1: Law of Inertia: Every body continues in its state of rest or of uniform speed in a straight line as long as no net force acts on it. N2:  F=ma: The acceleration of an object is directly proportional to the net force acting on it and is inversely proportional to its mass. Acceleration is in the same direction as the net force. N3: Action & Reaction: Forces are INTERACTIONS: Whenever one object exerts a force on a second object, the second exerts an equal and opposite force on the first. Physics Ch.4: Newton’s Laws

We derived Kepler’s 3d law (phenomenological) from Newton’s 2d (theory) Near the surface of the Earth, F=mg. Derive g from the mass M and size R of Earth: g is approximately constant close to the surface of the Earth, but weakens with altitude. Newton’s law is indistinguishable, in most cases, from Einstein’s insight that gravity is due to the curvature of space near massive objects. Physics Ch.6: Gravitation & Newton’s Synthesis

Astrophysics Ch.2:

Mon.26.Jan: Workshop on Jupiter’s moons & Dark matter Tues.27.Jan: HW due on Universe 3+4; Quiz Review Physics Ch.3+4; ML Physics Ch.6 Thus. 28.Jan: Lecture and ML on Astrophysics Ch.2 Tues.3.Feb: HW due on Physics Ch.6 & CO Ch.2; Quiz Learning Plan for weeks 3-4:

Assignments for week 4: Tues.27.Jan: HW due: Physics Ch.6 # 54 Universe Ch.3 # 23, 24, 33, 30, 43, start 45 Ch.4 # 36, 48, 52 (50), 35, 39, 44 Review Physics Ch.3+4; ML Physics Ch.6, Gravitation: Team 1: Ch.6.1-3, #13, 14: Brian & Mary Team 2: Ch.6.4-5, #28: Erin & Jenni Team 3: Ch.6.6-8, #47: Annie & Tristen Thus. 28.Jan: Lecture on Astrophysics Ch.2 Team 4: Ch , #2.1 & 2.2: Matt & Zita Team 5: Ch.2.3, #2.7: Joey & Jared Tues.3.Feb: HW due: Physics Ch.6 # 13, 14, 28, 47, 57, 60 CO (Astrophysics) Ch.2 # 1, 2, 7, 8, 11