Black holes can be characterized by their event horizons.

In summary, an event horizon is a boundary surrounding a black hole that marks the point of no return for anything that enters it. The size of a black hole's event horizon is determined by its mass and nothing can escape once it crosses the event horizon. Event horizons also affect time and gravity, causing time to slow down and gravity to become infinitely strong. There are different types of event horizons for different types of black holes, including the Schwarzschild, Reissner-Nordström, and Kerr event horizons.
  • #1
NOHK2710
1
0
a) If the sun were compressed sufficiently enough so that it would turn into a
black hole, what would be the event horizon of such an object expressed in
km?
b) What is the event horizon for a black hole with a mass of 10
9
Msol?
c) What is the event horizon for the black hole with a mass of 4•10
6
Msol
in the
center of our Galaxy
 
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  • #2
Welcome to PF!

Welcome to PF! :wink:

Show us what you've tried, and where you're stuck, and then we'll know how to help! :smile:
 

1. What is an event horizon?

An event horizon is a boundary surrounding a black hole beyond which nothing, not even light, can escape. It marks the point of no return for anything that enters the black hole.

2. How is the size of a black hole's event horizon determined?

The size of a black hole's event horizon is directly related to its mass. The more massive a black hole is, the larger its event horizon will be.

3. Can anything escape from inside a black hole's event horizon?

No, once something crosses the event horizon of a black hole, it is permanently trapped inside and cannot escape.

4. How do event horizons affect time and gravity?

Event horizons are where the effects of extreme gravity and time dilation become apparent. Time slows down and gravity becomes infinitely strong at the event horizon of a black hole.

5. Are there different types of event horizons?

Yes, there are several types of event horizons that can exist for different types of black holes. These include the Schwarzschild, Reissner-Nordström, and Kerr event horizons.

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