## Astronomy C

EKT26
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### Astronomy C

Starting off from last marathon:

A. What's the density of a schwarzschild black hole with a mass of 6.0E31 kg? (in kg/m^3)
B. Would this black hole be more or less dense than a more massive one?
C. What's the black hole's temperature
D. What would the wavelength of the emitted blackbody radiation be from a black body with the temperature from C? (in m)
E. How much would a black hole of this size bend light passing just above the schwarzschild radius? (in radians)
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Name
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### Re: Astronomy C

EKT26 wrote:
September 8th, 2020, 10:33 am
Starting off from last marathon:

A. What's the density of a schwarzschild black hole with a mass of 6.0E31 kg? (in kg/m^3)
B. Would this black hole be more or less dense than a more massive one?
C. What's the black hole's temperature
D. What would the wavelength of the emitted blackbody radiation be from a black body with the temperature from C? (in m)
E. How much would a black hole of this size bend light passing just above the schwarzschild radius? (in radians)
``` a. 2.024E19 kg/m^3
b. more dense
c. 2.045E-8 K
d. 1.417E5 m
e. uh 2 radians? not sure if this is right
```
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astronomybuff
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### Re: Astronomy C

Wait, how would you answer those questions? I'm only familiar with the formula for the scharzschild radius.

Name
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### Re: Astronomy C

astronomybuff wrote:
September 8th, 2020, 11:14 am
Wait, how would you answer those questions? I'm only familiar with the formula for the scharzschild radius.
a and b is just scharzschild a couple of times. this is useful for c. d is wiens law, and e I used the 2(Rs/R) formula given here but idk if that's right
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Favorite Past Events: Microbe, Invasive, Matsci, Fermi
Events!: Astro , Code , Fossils

2019-2020 Season
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Astro: 2/4/2/10/2/2/3
Code: 9/1/2/1/1/1/1
Fossils: 16/13/6/9/2/3/8

Success is not an option, it is an obligation.

astronomybuff
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### Re: Astronomy C

Sorry, I'm a bit slow. We are looking for the volume, so how does the schwarzchild formula give us that?

RiverWalker88
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### Re: Astronomy C

astronomybuff wrote:
September 8th, 2020, 12:38 pm
Sorry, I'm a bit slow. We are looking for the volume, so how does the schwarzchild formula give us that?
I believe you'd calculate the schwartzchild radius and then use that to calculate the volume of the sphere (not certain that's correct, that's how I'd do it)
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astronomybuff
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### Re: Astronomy C

Ohhh ty!

EKT26
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### Re: Astronomy C

Yup! That's correct! Last one was just a gut check

I always just found it interesting with how much you can do with such little information with black holes.

Also for the density one, since the volume is based off the mass too, you can just derive a "density equation" if you want to skip finding the schwarzschild radius.
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Bro. Fox Latin School: 2017-2019

Astronomy, Machines, Disease Detectives, and Ping-Pong Parachute are where I’m at.

EKT26
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### Re: Astronomy C

Name wrote:
September 8th, 2020, 11:03 am
EKT26 wrote:
September 8th, 2020, 10:33 am
Starting off from last marathon:

A. What's the density of a schwarzschild black hole with a mass of 6.0E31 kg? (in kg/m^3)
B. Would this black hole be more or less dense than a more massive one?
C. What's the black hole's temperature
D. What would the wavelength of the emitted blackbody radiation be from a black body with the temperature from C? (in m)
E. How much would a black hole of this size bend light passing just above the schwarzschild radius? (in radians)
``` a. 2.024E19 kg/m^3
b. more dense
c. 2.045E-8 K
d. 1.417E5 m
e. uh 2 radians? not sure if this is right
```
Kellenberg Memorial High School: 2020-2021
Bro. Fox Latin School: 2017-2019

Astronomy, Machines, Disease Detectives, and Ping-Pong Parachute are where I’m at.

RiverWalker88
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### Re: Astronomy C

Aight, I think it's probably time for a revive.
1. When Isaac Newton first began estimating distances to stars, he assumed that their brightness was only directly proportional to their distance. He calculated the distance to the star Sirius of about double the actual distance. What two incorrect assumptions did he make that lead to the incorrect quantity?
2. In order to correctly find the distance to Sirius, how would he go about calculating the distance?
Mr.Epithelium wrote:
September 10th, 2020, 3:07 pm
Some exciting new topics for 2021! Can we make this the longest chain again?
Let's try to exceed the length the Anatomy & Physiology question marathon, add some competition to this . We're already at a good start, with triple the posts. Can we streamline our lead?
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Mr.Epithelium (September 15th, 2020, 11:30 am)
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