Figure 6.71 shows the path of a comet orbiting a star.
(a) Rank-order the locations on the path in terms of the magnitude of the comet's momentum at each location, starting
with the location at which the magnitude of the momentum is the largest.
(b) Rank-order the locations on the path in terms of the comet's kinetic energy at each location, starting with the
location at which the kinetic energy is the largest.
(c) Consider the system of the comet plus the star. Which of the following statements are correct?
(A) External work must be done on the system to speed up the comet.
(B) As the comet slows down, energy is lost from the system.
(C) As the comet's kinetic energy increases, the gravitational potential energy of the system also increases.
(D) As the comet slows down, the kinetic energy of the system decreases.
(E) As the kinetic energy of the system increases, the gravitational potential energy of the system decreases.
(d) Still considering the system of the comet plus the star, which of the following statements are correct?
a. The sum of the kinetic energy of the system plus the gravitational potential energy of the system is a positive
number.
b. At every location along the comet's path the gravitational potential energy of the system is negative.
c. The gravitational potential energy of the system is inversely proportional to the square of the distance between
the comet and star.
d. The sum of the kinetic energy of the system plus the gravitational potential energy of the system is the same
at every location along this path.
e. Along this path the gravitational potential energy of the system is never zero.
(e) Rank-order the locations on the path in terms of the potential energy of the system at each location, largest first.
(Remember that −3 > −5).