Chapter 13 Flashcards Preview

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Flashcards in Chapter 13 Deck (14):
1

Which of these objects has the smallest radius?
a 1.2 white dwarf
a 0.6 white dwarf
Jupiter

a 1.2M white dwarf

2

Which of these isolated neutron stars must have had a binary companion?

a pulsar inside a supernova remnant that pulses 30 times per second
an isolated pulsar that pulses 600 times per second
a neutron star that does not pulse at all

an isolated pulsar that pulses 600 times per second

3

What would happen to a neutron star with an accretion disk orbiting in a direction opposite to the neutron star's spin?

its spin would slow down

4

From the viewpoint of an observer in the orbiting rocket, what happens to time on the other rocket as it falls toward the event horizon of the black hole?

Time runs increasingly slower as the rocket approaches the black hole.

5

As the falling rocket plunges toward the event horizon, an observer in the orbiting rocket would see that the falling rocket __________.

slows down as it approaches the event horizon, and never actually crosses the event horizon

6

you know that from afar we’ll never see the in-falling rocket cross the event horizon, yet it will still eventually disappear from view. Why?

Its light will become so redshifted that it will be undetectable.

7

If you were inside the rocket that falls toward the event horizon, you would notice your own clock to be running __________.

at a constant, normal rate as you approach the event horizon

8

If you were inside the rocket that falls toward the event horizon, from your own viewpoint you would __________.accelerate

accelerate as you fall and cross the event horizon completely unhindered

9

Which of these objects has the largest radius?

a 1.2 white dwarf
a 1.5 neutron star
a 3.0 black hole

1.2 M white dwarf

10

Which of these things has the smallest radius?
a 1.2 white dwarf
the event horizon of a 3 black hole
the event horizon of a 10 black hole

the event horizon of a 3M black hole

11

What would happen if the Sun suddenly became a black hole without changing its mass?

Earth's orbit would not change

12

How would a flashing red light appear as it fell into a black hole?

Its flashes would shift to the infrared part of the spectrum.

13

Which of these black holes exerts the weakest tidal forces on an object near its event horizon?
a 10 Mblack hole
a 100M black hole
a 10^6 M black hole

a 10^6 M black hole

14

Where do gamma-ray bursts tend to come from?

extremely distant galaxies