Question 1

In general,the narrower the spectral line of a star:

Accepted Answer

A)   the hotter the star is.
B)   the bigger the star is.
C)   the denser the star is.
D)   the smaller the star is.
E)   the cooler the star is. B

Question 2

The ________ magnitude of a star depends directly upon its luminosity and distance.

Accepted Answer

apparent

Question 3

In a binary system,the more massive stars always stay closer to the center of mass and move slower.

Accepted Answer

A) True 
 B)False  True

Question 4

What role does helium play in spectral classification?

Accepted Answer

The answer of What role does helium play in spectral...

Question 5

On the H-R diagram,the Sun lies:

Accepted Answer

A)   at the top left.
B)   at the bottom left.
C)   at the bottom right.
D)   about the middle of the main sequence.
E)   at the top right.

Question 6

For luminosity classification,fat stars have skinny spectral lines.

Accepted Answer

A) True 
 B)False

Question 7

Star A is a main sequence star of spectral type F2 and star B is a white dwarf of spectral type B4.Which statement below is correct?

Accepted Answer

A)   Star A appears brighter than star B.
B)   Star B appears brighter than star A.
C)   Star A is hotter than star B.
D)   Star B is hotter than star A.
E)   None of the above can be said about these two stars.

Question 8

On the main sequence,almost all stars have radii between about 0.1 and 10 times the Sun.

Accepted Answer

A) True 
 B)False

Question 9

Two red stars have surface temperatures of 3000 K,but Star A's luminosity is about 5% of the Sun's and Star B's luminosity is about 32,000 times the luminosity of the Sun.How much bigger is star B than star A?

Accepted Answer

A)   They are the same size.
B)   Star B's radius is about 16 times larger than star A's radius.
C)   Star B's radius is about 800 times larger than star A's radius.
D)   Star B's radius is about 640,000 times larger than star A's radius.
E)   This cannot be determined from the information given.

Question 10

What types of observations are necessary to determine the motion of a star through space?

Accepted Answer

The answer of What types of observations are necessary to...

Question 11

The vast majority of stars near us would fall to the bottom right on the H-R diagram.

Accepted Answer

A) True 
 B)False

Question 12

A nearby star has a parallax of 0.2 arc seconds.What is its distance?

Accepted Answer

A)   0.1 parsec
B)   0.2 parsec
C)   0.5 parsec
D)   5 parsecs
E)   50 parsecs

Question 13

If a star appears to move relative to other stars over a one-year period,this motion is due to the star's:

Accepted Answer

A)   transverse motion.
B)   radial motion.
C)   parallax shift.
D)   Doppler shift.
E)   true space motion.

Question 14

The Hipparcos mission's observations have given us good data on stars out to about:

Accepted Answer

A)   100 light years.
B)   200 light years.
C)   200 parsecs.
D)   1000 light years.
E)   1000 parsecs.

Question 15

The Hipparcos mission's data on parallaxes is useful for stellar distances out to about 200 pc.

Accepted Answer

A) True 
 B)False

Question 16

Having nothing to do with trigonometry,________ parallaxes use the width of absorption lines to estimate the star's luminosity and size and distance.

Accepted Answer

A)   bolometric
B)   photometric
C)   spectroscopic
D)   holographic
E)   videometric

Question 17

The apparent magnitude of the Sun is -26,while Sirius has an apparent magnitude of -1; how much brighter does the Sun appear than Sirius?

Accepted Answer

The answer of The apparent magnitude of the Sun is...

Question 18

If a star appears to move back and forth relative to other stars over a six-month period,this motion is due to the star's:

Accepted Answer

A)   transverse motion.
B)   radial motion.
C)   parallax shift.
D)   Doppler shift.
E)   true space motion.

Question 19

Why is the main sequence main? Why are these stars so common?

Accepted Answer

The answer of Why is the main sequence main? Why...

Question 20

How can the color index give the star's temperature?

Accepted Answer

The answer of How can the color index give the...

Exam 17: The Stars: Giants,Dwarfs,and the Main Sequence

In general,the narrower the spectral line of a star:

The ________ magnitude of a star depends directly upon its luminosity and distance.

In a binary system,the more massive stars always stay closer to the center of mass and move slower.

What role does helium play in spectral classification?

On the H-R diagram,the Sun lies:

For luminosity classification,fat stars have skinny spectral lines.

Star A is a main sequence star of spectral type F2 and star B is a white dwarf of spectral type B4.Which statement below is correct?

On the main sequence,almost all stars have radii between about 0.1 and 10 times the Sun.

Two red stars have surface temperatures of 3000 K,but Star A's luminosity is about 5% of the Sun's and Star B's luminosity is about 32,000 times the luminosity of the Sun.How much bigger is star B than star A?

What types of observations are necessary to determine the motion of a star through space?

The vast majority of stars near us would fall to the bottom right on the H-R diagram.

A nearby star has a parallax of 0.2 arc seconds.What is its distance?

If a star appears to move relative to other stars over a one-year period,this motion is due to the star's:

The Hipparcos mission's observations have given us good data on stars out to about:

The Hipparcos mission's data on parallaxes is useful for stellar distances out to about 200 pc.

Having nothing to do with trigonometry,________ parallaxes use the width of absorption lines to estimate the star's luminosity and size and distance.

The apparent magnitude of the Sun is -26,while Sirius has an apparent magnitude of -1; how much brighter does the Sun appear than Sirius?

If a star appears to move back and forth relative to other stars over a six-month period,this motion is due to the star's:

Why is the main sequence main? Why are these stars so common?

How can the color index give the star's temperature?