When the sun rises in the morning on December 20th and then rises again December 20th of the next year, Earth is said to have . revolved around the sun one time

revolved around the sun two times

rotated on its axis one time

rotated on its axis two times

Note: the following questions are unrelated to the balmer series or the martian. refer to your course notes. a sun-sized star will spend most of its lifetime as a: white dwarf b. red giant c. protostar d. main-sequence star

Aparticle moves in the xy plane with constant acceleration. at time zero, the particle is at x = 6 m, y = 8.5 m, and has velocity ~vo = (9 m/s) ˆı + (−2.5 m/s) ˆ . the acceleration is given by ~a = (4.5 m/s 2 ) ˆı + (3 m/s 2 ) ˆ . what is the x component of velocity after 3.5 s? answer in units of m/s.

Consider a double atwood machine constructed as follows: a mass 4m is suspended from a string that passes over a massless pulley on frictionless bearings. the other end of this string supports a second similar pulley, over which passes a second string supporting a mass of 3m at one end and m at the other. using two suitable generalized coordinates, set up the lagrangian and use the lagrange equations to find the acceleration of the mass 4m when the system is released. explain why the top pulley rotates even though it carries equal weights on each side.