Summary
- Torque & vector cross product
- Angular momentum
- Newton's Universal Law of Gravity
Walker5e CEx 12-7
The orbital speed of the Earth is greatest around January 4 and least around July 4.
Therefore, the distance from the Earth to the Sun on January 4 is ____ its distance from the Sun on July 4.
A. greater than
B. less than
C. equal to
Answer
PoP5 11.15mod
The mass of the earth is 5.97×1024 kg. What is the orbital period of a satellite whose
orbit radius is 4.2235×107 m?
A. 13.3 s
B. 3420 s
C. 13,800 s
D. 86,400 s
Answer
answer
B. less than
The law of equal areas (Kepler's second law) requires that the orbit
speed is greatest when the distance to the Sun is least. In the northern hemisphere we experience winter
in January even though the orbit distance is least, because the seasons are caused by the tilt of the
Earth's orbit axis with respect to the orbital plane, and not by the distance between the Earth and the
Sun.
answer
D. 86,400 s
