The RR Lyrae stars all have periods of
A) less than a second.
B) several minutes.
C) several hours.
D) several days.
E) several weeks.
C
You might also like to view...
There are a variety of units for power. Which of the following would be fitting units of power (though perhaps not standard)?
A) Watt B) Joule C) Joule/second D) HP
What is the purpose of interferometry?
A) It allows two or more small telescopes to achieve the angular resolution of a much larger telescope. B) It allows two or more small telescopes to achieve a larger light-collecting area than they would have independently. C) It is designed to prevent light pollution from interfering with astronomical observations. D) It reduces the twinkling of stars caused by atmospheric turbulence.
Compared with hang time on Earth, hang time on the Moon would be
A) less. B) the same. C) greater.
A 500 nm wavelength light illuminates a soap film with an index of refraction 1.33 to make it look bright. If the beam of light is incident normal on the film, what is the minimum thickness of the film?
A) 47.0 nm B) 74.0 nm C) 94.0 nm D) 152 nm E) 268 nm