FiltersDone

Question type

Essay

Multiple Choice

Short Answer

True False

Matching

Exam 10: Characterizing Stars

Show Answer

Share

---

All types

Filters

Study FlashcardsPractice ExamLearn

Question 1

Multiple Choice

Review LaterAdd Note

Review Later

The star Elnath is classified as B7 III and the star Al Na'ir is classified as B7 IV.Compared with Al Na'ir,Elnath has about the same:

A) surface temperature but is intrinsically much fainter.
B) intrinsic brightness but is considerably cooler.
C) surface temperature but is intrinsically much brighter.
D) intrinsic brightness but is considerably hotter.

Correct Answer

verified

C

Question 2

Multiple Choice

Review LaterAdd Note

Review Later

Luminosity is measured in:

A) watts.
B) watts per second.
C) watts per square meter.
D) parsecs.

Correct Answer

verified

Show Answer

Question 3

Multiple Choice

Review LaterAdd Note

A star of apparent magnitude -1.5 appears _____ than a star of apparent magnitude +2.0.

A red supergiant star is found to have a surface temperature of 2500 K and a luminosity 100,000 times that of the Sun.Use the Hertzsprung-Russell diagram in Figure 10-8 of Comins,Discovering the Essential Universe,6th ed.,to determine its approximate radius compared with that of the Sun.

Two of the brightest stars in Orion are Betelgeuse (apparent magnitude = 0.45) and Rigel (apparent magnitude = 0.15) .From this information,you can determine that Betelgeuse is:

For most stars,the:

The spectral luminosity class of the star α Arae is B2 V,and that of π Herculi is K3 II.Using only this information,without referring to tables or diagrams,we can tell that α Arae is:

The following expressions are parameters of stars that astronomers obtained from their measurements.Which of these conclusions is obviously NOT correct,based on the positions of these stars on the Hertzsprung-Russell diagram in Figure 10-8 of Comins,Discovering the Essential Universe,6th ed.? (L⊙ and R⊙ are the luminosity and radius of the Sun,respectively.)

A star has an absolute magnitude M = 1.69 and an apparent magnitude m = 1.04.How far away is this star? (Hint: this question does not require a detailed calculation.)

If a certain star shows a strong absorption spectrum in hydrogen Balmer lines,the surface temperature of the star is hot enough that collisions between atoms there:

As you move upward and to the right on the H-R diagram,stars become:

If you look out at a clear night sky with the unaided eye,the faintest stars you can see have magnitudes around:

The spectral luminosity class of the star Spica is B1 V,and that of the starƮ Ceti is G8 V.From this information,we know thatƮ Ceti is _____ Spica.

Which spectral classification letter signifies the hottest stellar surface temperature?

How many electrons are missing from the ionized silicon atom Si IV?

White dwarfs are not included in the luminosity classification because they are:

Compared with a star in the middle of the Hertzsprung-Russell diagram,a star in the upper right of the diagram is:

Which statement comparing the Sun with the giant stars is NOT true? (Refer to Figure 10-10,Comins,Discovering the Essential Universe,6th ed.)

An astronomer is measuring the brightness of a particular star through a telescope,using different filters in the visual (yellow-green) ,violet,and ultraviolet regions.What is the name of the technique being used by this astronomer?

Which major perturbation can occur to a close binary system and radically alter the evolution and behavior of the two individual stars?