Question

check please
If the mass of a star is 6 x 10^50kg, what would be the mass of the black hole formed if the star collapsed?
A) 6 x 10^50kg
B) 6.67 x 10^-11kg
C) It would depend upon the radius of the black hole
D) 0 kg
i said its A
and one more
If the star described in the question above exerted a gravitational force on an orbiting planet of 10^20 N,what gravitational force would it exert on the planet if the star collapsed to form a black hole?
A) 10^20N
B) much greater than 10^20N
C) much less than 10^20 N
D) there is not enough information given to answer this question

Answer 1

i said A for the second one as well

Answer 2

I would say it is OK, for both questions. (In the first, mass doesn't change, only the density varies, and in the second, the force always is calculated as if the mass were concentrated in the center of the bodies)

Answer 3

thank you for lookin at it for me :)