- 3 A Star Which Has A Mass Of 4 60x10 Kg And A Radius Of 9 30x10 M Rotates On Its Axis Once Every 16 0 Days Wilt Is 1 (46.23 KiB) Viewed 48 times
3. A star, which has a mass of 4.60x10** kg and a radius of 9.30x10 m, rotates on its axis once every 16.0 days Wilt is the moment of inertia ur this stat? (ans. I - 1.59:10" kgm") b. What is the angular velocity of this star? (ans: - 4.55x10* rad/s) What will be the linear velocity of a sunspot that is located on the equator of this star? (ans: v= 4.23x10 m/s) d. What is the angular momentum of this star? Cans: L = 7:23x10 kgm/s) As this star finally consumes most of its Hydrogen fuel it starts to contract and heat up until it gets hot enough to start burning Helium as a fuel. The burning of the Helium fuel is very intense and the star quickly becomes a "red giant as it expands to a new radius of 4.65x109 m. t. What will be the angular momentum of this star after it has expanded into a red giant? (ans: L = 7,23x104 kgm/s) t. What will be the angular velocity of the star after it has expanded into a red giant? (ans:w = 1.82x10' rad/s) & What will be the new rotational period of this star after it has become a red giant? (ans: T=400 days) After a few million years the Helium fuel is all used up and the star again begins to contract, becomes extremely hot and then undergoes a massive supernova explosion. After the explosion the remaining neutron star has a radius of only 1 200 km. [Assume that the mass of the star remains unchanged.) h. What will be the angular momentum of this star after it has collapsed into a neutron star? (ans: L = 7.23x10 kgm/s) i. What will be the moment of inertia of this star after it has collapsed into a neutron star? (ans:/= 2.65x10kem') What will be the angular velocity of this star after it has collapsed? (ans: a = 2.73 rad/s) k What will be the rotational period of this star after it has collapsed? (ans:T= 2.30 s)