# Physics

posted by .

Black Holes are suspected when a visible star is being noticeably pulled by an invisible partner that is more than 3 times as massive as the Sun. A red giant star is accelerated in a linear direction by gravity at 0.075 m/s2 towards an object that is 9.4 x1010 m away.

a) What is the mass of the invisible star? Answer using scientific notation (eg. 1e+10)
b) By what factor is the star more massive than our Sun? Answer in decimal.

• Physics -

F = GMm/r^2
a = F/m = GM/r^2 = 6.673*10^-11 * M / (9.4*10^10)^2 = 0.075
M = 9.931*10^30

M/sun = 9.931*10^30 / 1.989*10^30 = 4.993

so, the red giant is 5 times as massive as Sol.

• Physics -

;,ee;ffnlqgnfqlg'wtlgqrmg;g;

## Similar Questions

1. ### physics

Sun will turn into a red giant star one day. Today the sun has a mass of 2*10^30kg and a radius of 70km and an angular velocity of 2.85*10^-6 rad/s. How fast are the particles moving at the surface of the sun?
2. ### Physics

Hunting a black hole. Observations of the light from a certain star indicate that it is part of a binary (two-star) system. This visible star has orbital speed v = 270 km/s, orbital period T = 1.6 days, and approximate mass m1 = 6.0Ms, …
3. ### English

Which sentence contains repetitious words that should be left out?
4. ### physics

A small rock passes a massive star, following the path shown in red on the diagram above. When the rock is a distance 4e+13 m (indicated as d1 on the diagram) from the center of the star, the magnitude of its momentum p1 is 1.1e+17 …
5. ### earth science

Stellar evolution is the life cycle of a star. A cycle suggests that upon death of a star, another star is born. How is this possible?
6. ### science help

Which of the following is a massive star that has reached the end of its stellar evolution?
7. ### science help PLS

Which of the following is a massive star that has reached the end of its stellar evolution?
8. ### SCIENCE HELP PLEEASE

Given the following images, choose the one that most likely represents an O-class star. Star A is a yellow star. Star B is a blue star. Star C is a red star. Star D is a green star. A B C D is it b
9. ### science

Using various telescopes, astronomers discovered a giant star that is 100 times larger than the Sun, and is very hot. It is blue-white in color. Why does the Sun appear brighter than this larger star when viewed from Earth?
10. ### science

Using various telescopes, astronomers discovered a giant star that is 100 times larger than the Sun, and is very hot. It is blue-white in color. Why does the Sun appear brighter than this larger star when viewed from Earth?

More Similar Questions