Astronomy clicker question: Mars finding

Astronomy 210, Fall Semester 2008
Cuesta College, San Luis Obispo, CA

Students were asked the following clicker question (Classroom Performance System, einstruction.com) at the end of their learning cycle:

Consider Mars and the Earth in their orbits as shown below. (This drawing is not to scale, and orbits have been simplified as circles instead of ellipses.)


The position of Mars in the San Luis Obispo, CA sky is:
(A) near the east horizon, at sunset.
(B) near the west horizon, at sunset.
(C) near the east horizon, at sunrise.
(D) near the west horizon, at sunrise.
(E) (None of the above choices, as Mars would not be visible anywhere in the San Luis Obispo, CA sky at sunset nor sunrise.)
(F) (I'm lost, and don't know how to answer this.)

Section 70160
(A) : 12 students
(B) : 6 students
(C) : 2 students
(D) : 10 students
(E) : 0 students
(F) : 0 students

This question was asked again after displaying the tallied results with the lack of consensus, with the following results. No comments were made by the instructor, in order to see if students were going to be able to discuss and determine the correct answer among themselves.

Section 70160
(A) : 27 students
(B) : 1 student
(C) : 1 student
(D) : 0 students
(E) : 0 students
(F) : 0 students

Correct answer: (A)

Mars is not visible at sunrise. However, it is visible at sunset, rising from the east horizon as the Sun sets in the west.

Pre- to post- peer-interaction gains:
pre-interaction correct = 40%
post-interaction correct = 93%
Hake (normalized) gain <g> = 89%