Question 1

The ____ of a black hole is the radius from a black hole at which the escape velocity is approximately equal to the speed of light.

Accepted Answer

A)  Roche limit 
B)  Lagrangian point 
C)  Chandraskhar limit 
D)  Hubble radius 
E)  event horizon 
A)  Roche limit 
B)  Lagrangian point 
C)  Chandraskhar limit 
D)  Hubble radius 
E)  event horizon

Question 2

If the inner accretion disk around a black hole has a temperature of 106 K, at what wavelength will it radiate the most energy? Hint: wavelength in nm =3,000,000/T in K

Accepted Answer

A)  106 nm 
B)  3 nm 
C)  3*106 nm 
D)  1 nm 
E)  3*1011 nm 
A)  106 nm 
B)  3 nm 
C)  3*106 nm 
D)  1 nm 
E)  3*1011 nm

Question 3

If the sun and stars are supported by gas pressure, what supports a neutron star?

Accepted Answer

A neutron star is supported against grav

Question 4

Theory predicts that neutron stars may not exceed 3 solar masses.

Accepted Answer

A) True 
 B)False

Question 5

The Schwarzschild radius of a 1-   black hole is approximately

Accepted Answer

A)  3 km. 
B)  1,500,000 km, the size of the sun. 
C)  150,000,000 km or 1 AU. 
D)  3*13 km or 1 pc. 
A)  3 km. 
B)  1,500,000 km, the size of the sun. 
C)  150,000,000 km or 1 AU. 
D)  3*13 km or 1 pc.

Question 6

Many pulsars have periods that are gradually increasing as the spinning neutron stars lose energy.

Accepted Answer

A) True 
 B)False

Question 7

The figure shows an image of an isolated black hole. A black hole emits

Accepted Answer

A)  light with wavelengths in the black color region. 
B)  no light from inside the event horizon. 
C)  light which is blueshifted to shorter wavelengths as it escapes. 
D)  light which is redshifted to shorter wavelengths as it escapes. 
A)  light with wavelengths in the black color region. 
B)  no light from inside the event horizon. 
C)  light which is blueshifted to shorter wavelengths as it escapes. 
D)  light which is redshifted to shorter wavelengths as it escapes.

Question 8

A pulsar requires that a neutron star

Accepted Answer

A)  I & III 
B)  I & IV 
C)  II, III, & IV 
D)  I, III, & IV 
E)  I, II, III, & IV 
A)  I & III 
B)  I & IV 
C)  II, III, & IV 
D)  I, III, & IV 
E)  I, II, III, & IV

Question 9

Pulsars cannot be spinning white dwarfs because

Accepted Answer

A)  white dwarfs are not that common. 
B)  white dwarfs are not dense enough. 
C)  white dwarfs do not have magnetic fields. 
D)  a white dwarf spinning that fast would fly apart. 
E)  all of the above. 
A)  white dwarfs are not that common. 
B)  white dwarfs are not dense enough. 
C)  white dwarfs do not have magnetic fields. 
D)  a white dwarf spinning that fast would fly apart. 
E)  all of the above.

Question 10

How can an old pulsar have a very short pulsar period, say less than 0.03 seconds?

Accepted Answer

The answer of How can an old pulsar have a...

The ____ of a black hole is the radius from a black hole at which the escape velocity is approximately equal to the speed of light.

If the inner accretion disk around a black hole has a temperature of 10⁶ K, at what wavelength will it radiate the most energy? Hint: wavelength in nm =3,000,000/T in K

If the sun and stars are supported by gas pressure, what supports a neutron star?

Theory predicts that neutron stars may not exceed 3 solar masses.

The Schwarzschild radius of a 1- black hole is approximately

Many pulsars have periods that are gradually increasing as the spinning neutron stars lose energy.

The figure shows an image of an isolated black hole. A black hole emits

A pulsar requires that a neutron star

Pulsars cannot be spinning white dwarfs because

How can an old pulsar have a very short pulsar period, say less than 0.03 seconds?

Here and Now

A Users Guide to the Sky

Cycles of the Sun and Moon

The Origin of Modern Astronomy

Light and Telescopes

Atoms and Spectra

The Sun

The Family of Stars

The Formation and Structure of Stars

The Deaths of Stars

The Milky Way Galaxy

Galaxies: Normal and Active

Modern Cosmology

The Origin of the Solar System

Earth and Moon: Bases for Comparative Planetology

Mercury, Venus and Mars

The Outer Solar System

Meteorites, Asteroids, and Comets

Astrobiology: Life on Other Worlds

Filters

Exam 11: Neutron Stars and Black Holes

The ____ of a black hole is the radius from a black hole at which the escape velocity is approximately equal to the speed of light.

If the inner accretion disk around a black hole has a temperature of 106 K, at what wavelength will it radiate the most energy? Hint: wavelength in nm =3,000,000/T in K

If the sun and stars are supported by gas pressure, what supports a neutron star?

Theory predicts that neutron stars may not exceed 3 solar masses.

The Schwarzschild radius of a 1- black hole is approximately

Many pulsars have periods that are gradually increasing as the spinning neutron stars lose energy.

The figure shows an image of an isolated black hole. A black hole emits

A pulsar requires that a neutron star

Pulsars cannot be spinning white dwarfs because

How can an old pulsar have a very short pulsar period, say less than 0.03 seconds?

Here and Now

A Users Guide to the Sky

Cycles of the Sun and Moon

The Origin of Modern Astronomy

Light and Telescopes

Atoms and Spectra

The Sun

The Family of Stars

The Formation and Structure of Stars

The Deaths of Stars

The Milky Way Galaxy

Galaxies: Normal and Active

Modern Cosmology

The Origin of the Solar System

Earth and Moon: Bases for Comparative Planetology

Mercury, Venus and Mars

The Outer Solar System

Meteorites, Asteroids, and Comets

Astrobiology: Life on Other Worlds

Filters

If the inner accretion disk around a black hole has a temperature of 10⁶ K, at what wavelength will it radiate the most energy? Hint: wavelength in nm =3,000,000/T in K