Physics question about black holes and determing their mass?

AI Thread Summary
To determine the mass of a black hole with a Schwarzschild radius of 15.4 km, the equation Rsch = 2GM/c^2 is used. The user attempted to isolate M but received a different answer, indicating confusion about how to express the mass in terms of solar masses. The discussion highlights that "one solar mass" equals approximately 1.988435×10^30 kilograms, which is essential for calculating the ratio of the black hole's mass to the sun's mass. The user is uncertain whether the black hole's mass is 2, 3, or 0.5 solar masses. Understanding these calculations is crucial for accurately relating black hole mass to solar mass.
Hannahj1
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Homework Statement


a black hole has schwarzschild radius of 15.4km what is the mass of the black hole in terms of the suns mass?

Homework Equations


Rsch = 2GM/c^2

The Attempt at a Solution


I plugged values into the equation and isolated for M and it gave me a different answer. Idk how the suns mass relates to the equation/answer
 
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I think they want the ratio so you know the BH mass and you can find the suns mass and then compute the ratio.

Is it 2 solar masses or 3 or even 1/2... ?
 
In astronomy, "one solar mass" is a unit of mass = 1.988435×1030 kilograms. The sun's mass is "one solar mass". For example, the star Arcturus has a mass of 2.3*1030 kg - 1.1 solar masses

Does that help?
 

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