Question 1

At what point in the light curve below is the cooler star in front of the hotter star?

Accepted Answer

The answer of At what point in the light curve...

Question 2

The total mass of a binary system can be calculated from

Accepted Answer

The mass of a binary system can be calculated using Kepler's third law, which relates the period and semimajor axis of the orbit to the total mass of the system. This law assumes that the two stars in the binary system are orbiting around their center of mass, which is also the center of the orbit. Therefore, by measuring the period and semimajor axis of the binary system, we can calculate the total mass of the system.

Question 3

The diagram below illustrates two stars in a visual binary system and the center of mass of this system. Based on this diagram, what is the ratio of the mass of star A to the mass of star B?

Accepted Answer

The answer of The diagram below illustrates two stars in...

Question 4

A spectroscopic binary shows periodic variations in its

Accepted Answer

A spectroscopic binary refers to a binary star system where the orbital motion of the stars causes periodic shifts in their spectral lines. This is known as the radial velocity method and is used to detect exoplanets as well. Therefore, the best choice for periodic variations in a spectroscopic binary would be its radial velocity.

Question 5

Table 8-1
Use the chart below to answer the following question(s).
 
-From the data given,, which star in Table 8-1 has the greatest surface temperature?

Accepted Answer

HR 4621 has the highest surface temperature of 40,000 K, which is the maximum value in the table.

Question 6

What is the total mass of a binary star system with P = 20 yr and a = 10 AU?

Accepted Answer

According to Kepler's third law, $P^2=\frac{4\pi^2 a^3}{G(m_1+m_2)}$. Rearranging this equation to solve for $m_1+m_2$, we get $(m_1+m_2)=\frac{4\pi^2a^3}{GP^2}$. Plugging in the values given, we get $(m_1+m_2)=\frac{4\pi^2(10	ext{ AU})^3}{G(20	ext{ yr})^2}=2.514	ext{ solar masses}$. Therefore, the answer is B) 2.5 solar masses.

Question 7

From the mass-luminosity relation, a 2-solar-mass star on the main sequence would have a luminosity of approximately ____ solar luminosities.

Accepted Answer

According to the mass-luminosity relation, a star with twice the mass of the sun would have a luminosity of approximately 11 times that of the sun. Therefore, the correct answer is (C) 11.

Question 8

Table 8-2
Use the chart below to answer the following question(s).
 
-Which star in Table 8-2 has the greatest surface temperature?

Accepted Answer

Surface temperature is indicated by the spectral type, with O being the hottest and M being the coolest. Among the choices given, (F1F1F1S1F1F1F10 Cen) has the spectral type of F9, which is hotter than the spectral types of the other stars listed.

Question 9

If a star with an absolute magnitude of -5 has an apparent magnitude of +5, then its distance is

Accepted Answer

The answer of If a star with an absolute magnitude...

Question 10

Table 8-1
Use the chart below to answer the following question(s).
 
-From the data given,, which star in Table 8-1 has the greatest diameter?

Accepted Answer

The answer of Table 8-1
Use the chart below to answer...

Question 11

If a star has a parallax of 0.02 seconds of arc, then its distance is

Accepted Answer

The distance in parsecs (pc) can be calculated as the inverse of the parallax angle in arcseconds. Therefore, 1/0.02 = 50 pc.

Question 12

Table 8-1
Use the chart below to answer the following question(s).
 
-From the data given, which star in Table 8-1 is the closest to Earth?

Accepted Answer

The answer of Table 8-1
Use the chart below to answer...

Question 13

The diagram below shows the radial velocity curve of a double-line spectroscopic binary. Based on this radial velocity curve, which of the following statements is correct?

Accepted Answer

The radial velocity curve of a double-line spectroscopic binary shows the velocity variations of both stars as they orbit around a common center of mass. The amplitude of the velocity variations depends on the masses of the stars and their separation, with larger masses and closer separations resulting in larger amplitudes.

In this particular curve, it can be seen that the velocities of both stars vary sinusoidally over a period of approximately 2 days. However, the amplitude of the variations for Star B (the lower curve) is larger than for Star A (the upper curve). This indicates that Star B is more massive than Star A, since larger masses result in larger amplitudes of velocity variations.

To determine the relative masses of the stars, we can use the fact that the ratio of their masses is equal to the ratio of the semi-amplitudes of their velocity variations. In this case, the semi-amplitude of Star B's velocity variations is approximately twice that of Star A's. Therefore, we can conclude that:

B) Star B is twice the mass of star A.

Question 14

Table 8-1
Use the chart below to answer the following question(s).
 
-From the data given,, which star in Table 8-1 has the greatest luminosity?

Accepted Answer

The answer of Table 8-1
Use the chart below to answer...

Question 15

Table 8-2
Use the chart below to answer the following question(s).
 
-Which star in Table 8-2 has the greatest diameter?

Accepted Answer

HD 39801, also known as Betelgeuse, is a red supergiant star known for its massive size, making it the star with the greatest diameter among the options listed.

Question 16

An eclipsing binary has been analyzed and it has been determined that the ratio of the mass of star A to the mass of star B is 6 and the total mass of the two stars is 26 solar masses. What are the masses of star A and star B?

Accepted Answer

The answer of An eclipsing binary has been analyzed and...

Question 17

Table 8-1
Use the chart below to answer the following question(s).
 
-From the data given, which star in Table 8-1 would appear the faintest in the night sky?

Accepted Answer

The star with the highest absolute magnitude is the faintest in the night sky. According to the chart, 65 Tau has an absolute magnitude of 5.7, which is the highest among the listed stars. Therefore, it would appear the faintest in the night sky.

Question 18

Table 8-2
Use the chart below to answer the following question(s).
 
-Which star in Table 8-2 is the closest to Earth?

Accepted Answer

9 CMa, also known as VY Canis Majoris, is one of the closest stars to Earth among the options listed.

Question 19

If the orbital velocity of an eclipsing binary is 97 km/s and the smaller star is completely eclipsed in 2 hours, what is the diameter of the smaller star?

Accepted Answer

The answer of If the orbital velocity of an eclipsing...

Question 20

In the light curve below, what is the period of the eclipsing binary?

Accepted Answer

The answer of In the light curve below, what is...

Quiz 8: The Family of Stars

At what point in the light curve below is the cooler star in front of the hotter star?

The total mass of a binary system can be calculated from

The diagram below illustrates two stars in a visual binary system and the center of mass of this system. Based on this diagram, what is the ratio of the mass of star A to the mass of star B?

A spectroscopic binary shows periodic variations in its

What is the total mass of a binary star system with P = 20 yr and a = 10 AU?

From the mass-luminosity relation, a 2-solar-mass star on the main sequence would have a luminosity of approximately ____ solar luminosities.

If a star with an absolute magnitude of -5 has an apparent magnitude of +5, then its distance is

If a star has a parallax of 0.02 seconds of arc, then its distance is

The diagram below shows the radial velocity curve of a double-line spectroscopic binary. Based on this radial velocity curve, which of the following statements is correct?

An eclipsing binary has been analyzed and it has been determined that the ratio of the mass of star A to the mass of star B is 6 and the total mass of the two stars is 26 solar masses. What are the masses of star A and star B?

Table 8-2 Use the chart below to answer the following question(s) . $Table 8-2 Use the chart below to answer the following question(s) . -Which star in Table 8-2 is the closest to Earth? A) ( \delta Cen) B) HR 4607 C) HR 4758 D) HD 39801 E) 9 CMa$ -Which star in Table 8-2 is the closest to Earth?

If the orbital velocity of an eclipsing binary is 97 km/s and the smaller star is completely eclipsed in 2 hours, what is the diameter of the smaller star?

In the light curve below, what is the period of the eclipsing binary?

Quiz 8: The Family of Stars

At what point in the light curve below is the cooler star in front of the hotter star?

The total mass of a binary system can be calculated from

The diagram below illustrates two stars in a visual binary system and the center of mass of this system. Based on this diagram, what is the ratio of the mass of star A to the mass of star B?

A spectroscopic binary shows periodic variations in its

Table 8-1 Use the chart below to answer the following question(s) . -From the data given,, which star in Table 8-1 has the greatest surface temperature?

What is the total mass of a binary star system with P = 20 yr and a = 10 AU?

From the mass-luminosity relation, a 2-solar-mass star on the main sequence would have a luminosity of approximately ____ solar luminosities.

Table 8-2 Use the chart below to answer the following question(s) . -Which star in Table 8-2 has the greatest surface temperature?

If a star with an absolute magnitude of -5 has an apparent magnitude of +5, then its distance is

Table 8-1 Use the chart below to answer the following question(s) . -From the data given,, which star in Table 8-1 has the greatest diameter?

If a star has a parallax of 0.02 seconds of arc, then its distance is

Table 8-1 Use the chart below to answer the following question(s) . -From the data given, which star in Table 8-1 is the closest to Earth?

The diagram below shows the radial velocity curve of a double-line spectroscopic binary. Based on this radial velocity curve, which of the following statements is correct?

Table 8-1 Use the chart below to answer the following question(s) . -From the data given,, which star in Table 8-1 has the greatest luminosity?

Table 8-2 Use the chart below to answer the following question(s) . -Which star in Table 8-2 has the greatest diameter?

An eclipsing binary has been analyzed and it has been determined that the ratio of the mass of star A to the mass of star B is 6 and the total mass of the two stars is 26 solar masses. What are the masses of star A and star B?

Table 8-1 Use the chart below to answer the following question(s) . -From the data given, which star in Table 8-1 would appear the faintest in the night sky?

Table 8-2 Use the chart below to answer the following question(s) . -Which star in Table 8-2 is the closest to Earth?

If the orbital velocity of an eclipsing binary is 97 km/s and the smaller star is completely eclipsed in 2 hours, what is the diameter of the smaller star?

In the light curve below, what is the period of the eclipsing binary?

Table 8-2 Use the chart below to answer the following question(s) . $Table 8-2 Use the chart below to answer the following question(s) . -Which star in Table 8-2 is the closest to Earth? A) ( \delta Cen) B) HR 4607 C) HR 4758 D) HD 39801 E) 9 CMa$ -Which star in Table 8-2 is the closest to Earth?