Here are the assignments for the math 21a physics section taught by
Spiro, when they are substantially different from the
assignments posted for other sections:
| Assigned in
class on: |
Assignment
Due Date: |
Reading | Problems | Solutions |
| Friday 2/22 | Wed 2/27 | 10.2 and 10.3 | Section 10.2 #6, 18, 21, 40, 41, 42, 45
Section 10.3 #2, 4 and the two problems posted below |
Friday 2/22 extra problems due Wednesday 2/27:
1) The distance from the Earth to the Sun is approximately 150 million kilometers. Asssume the Earth's orbit is circular. Comet Halley approaches perihelion (closest point to the Sun) once every 76 years. What is the semi-major axis of its orbit? (Use no other information to do this problem)
2) The distance from Earth to the Moon is approximately 385,000 kilometers.
The period of revolution of the Moon around the Earth is 29 days.
How high above the surface of the Earth should a communications satellite
be to always be above the same position? Assume that the satellite
is in an orbit perpendicular to the axis of rotation of the Earth and take
the radius of the Earth to be 6400 km. (This is called a Clarke geosynchronous
orbit, named after the science fiction writer Arthur C. Clarke, who proposed
the idea in 1948. The first such satellite was launched in 1963.)
Assume both orbits are circular.