Ask a Physicist 2. Black Holes

Video explaining what Black Holes are, where they come from and how we detect them.

Fore more information see:

http://cosmology.berkeley.edu/Education/BHfaq.html
- A very interesting and well written article by Tedd Bunn

http://antwrp.gsfc.nasa.gov/htmltest/rjn_bht.html
- A more complex artticle, but with interesting videos

http://uk.youtube.com/watch?v=pF63fxXMKTM
- A Documentary on Stephen Hawking and Black Holes

http://uk.youtube.com/watch?v=Y4ZDEdgtoDY&feature=related
- A Documentary on the discovery of Super Massive Black Holes

http://www.liveleak.com/view?i=b01_1187080995
- A Documentary about the life and death of stars

Some cool videos:
http://uk.youtube.com/watch?v=hoLvOvGW3Tk

Category:

Education

Tags:

• Black
• Holes
• black
• hole
• physics
• Gravity
• Space
• ask
• physicist
• escape
• velocity
• event
• horizon
• space
• time

[bdogshredder]

Zat vas EXELLENT! I especially liked the hole-puncher in space!-Classic!!

[ASKaPHYSICIST]

@bdogshredder thanks, I thought that was quite clever myself *pat on the back*

[E5YER1]

you know you dont have to speak like that to be smart

[ASKaPHYSICIST]

@E5YER1 How would you like me to speak instead?

[Dan0101010101010]

Why did you say a black hole is infinitely dense? Wouldn't a super massive black hole have a higher density than a normal black hole?

Also since not even light can escape a black hole could that level of force speed up a photon to a speed faster than the speed of light? For example if a photon was traveling right towards the black hole would its speed not increase as it got closer to the black hole?

Thanks for the video! :)

[ASKaPHYSICIST]

@Dan0101010101010 1stly, yes, it would be weightless.

2ndly no, it's just greater mass all in one spot. That's hole point of collapsing under once mass. All the forces which would normally hold stuff apart and give it a volume are over powered.

3rdly no, but the explanation why requires a more detailed explanation than I have provided here.

[ASKaPHYSICIST]

@4ATIME2BE1 I gave you the speed in m/s i.e. METERS per second. I would appreciate you spend your time looking at videos more suited to your current stage of education. Thanks.

[ASKaPHYSICIST]

@lovehate399 They are singular points of infinite density

[DJChronicx]

If the hawking radiation theory is correct, does the particle that escapes the black hole exceed the speed of light? 

[Dan0101010101010]

@ASKaPHYSICIST Thanks for the reply mate! :)

[cronicd21]

If there was a small empty space in the direct centre of the earth, and and object was placed in the direct middle of the empty space. Would it float and be in some kind of internal orbit? I'm not sure exactly what would happen to it