Question

 

As a star ages, it will undergo a variety of changes. One of the last phases of a large star's life is to gravitationally collapse its mass into a black hole of the same mass. Assuming the Sun was capable of becoming a black hole (it isn't), was would happen to the orbits of planets in our solar system if it becomes a black hole.

(Of course, this assumes that the planets are unaffected by prior stages of the Sun's evolving stages and that the Sun retains all of it's mass)

explain your answer.

Select one:

a. The orbits stay the same, but everything would be pulled closer to the Sun.

b. The orbits of the small planets would be sucked closer to the Sun, but the large planets would be unaffected.

c. The orbits of the small planets would be unaffected, but the large planets would be flung off into outer space.

d. The orbits would change, but the planets would remain in orbit around the Sun.

e. The orbits would remain the same, nothing would happen.

f. The orbits would change and the planets would be flung off into outer space.

2)

State the Reaction force for each.

a) A person pushes on a wall and exerts a force of 25 N [N]

b) A 2545 kg car is placed on a level surface.

3) Your car has a mass of 2400 kg.What is its weight?

4)Calculate the force between a 40.0 kg ballerina and the earth. (The mass of the earth is 5.98 x 10²⁴kg and the radius of the earth is 6.38 x 10⁶m)

5)Mars (mass of 6.39 x 10²³kg) orbits the Sun (mass of 1.99 x 10³⁰kg) at a distance of 227.9 million km. At what speed does Mars orbit the Sun?

Answer 1

1. "e" - Correct option ,the orbits would remain same ,nothing would hgappen.

it happens because gravitational force between two oobjects always depends upon the mass of two objects and the separation of centers of two object. The force does not depend upon how the masses are distributed upon the two objects .when sun converts into black hole its all mass concentrates in a very small distance but total mass of the sun remains same. Hence it exerts same force as before on other planets so the orbits will remain same.