Which of the following is correct for a stabl( aoh(yhrq,uvhh / 9g+e star?

  1.A star X is burning ca) 9 ,6hkbvva0el8dalirbon in its core. The reaction is given by:
$^{12}_{6}C$+$^{12}_{6}C$→$^{24}_{12}​Mg$
The following data are available for the reaction.
Rest mass of the$^{12}_{6}C$= 12.0111507u
Rest mass of the$^{24}_{12}​Mg$= 23.9909630u
Determine, in MeV, the energy released in the reaction. Be sure to express your answer to the correct number of significant figures. $ΔE$ =    MeV
2.The star Y is a red supergiant. State the next steps in the evolutionary sequence of the star Y.
3.Outline why the sun is not expected to undergo carbon fusion.

  Which of the following is correct about a red giant star?hh8hzb.-6 uiz
I. The orbits of the inner planets of the solar system and could fit into the volume of it
II. Cooler than the Sun
III. Have higher luminosity than the Sun

  1.VV Cephei is a binary star system composed o; 9z37hfurc../ oty yscazv:qf two stars referred to as VV Cephei A and VV Cephei B3;z o.y.uqav9z fhcc7yt /r s:.
(1)The measured wavelength of the peak spectral line of VV Cephei A is 760 nm. Show that the surface temperature of VV Cephei A is approximately 3800 K. T =    K
(2)The surface temperature of the Sun is $T_⊙$​=5800 K. The luminosity of the VV Cephei A is $2.7\times10^5$ times the Sun's luminosity $L_⊙$​. Determine the radius of VV Cephei A in terms of the Sun's radius $R_⊙$​. R =    $R_⊙$​
3.A Herzsprung-Russel (HR) diagram is shown.


Plot the current position of VV Cephei A on the HR diagram and identify the classification of VV Cephei A.
2.The mass of VV Cephei B is about 11 times the mass of the Sun and it is not on the main sequence.
(1)In terms of forces, explain the condition that causes a star to first leave the main sequence.2
(2)Explain why VV Cephei B is likely to remain on the main sequence for a shorter time than the Sun.2
(3)The parallax angle for VV Cephei B is 0.31 arcseconds. Calculate, in light years, the distance between the earth and VV Cephei B.2. d =    ly
(4)State why the parallax method is not suitable for measuring the distance of very distant stars.

  A main sequence star has a mbw 6hlmq )m)n(ass greater than 4 times the mass of the Sun. Which of the following is co) wlh(bn)qm m6rrect about the possible the fate of the star?
I. White dwarf
II. Neutron star
III. Black hole

  A star with a mass of twice the masr+( ;aiy p+d5a rbq-mos of the sun is a main sequence star. The time the sun is expected to spend in the main sequence is T. Which of the following is correct f5yp-+ bd ra iar(;+mqoor the time the star is expected to spend in the main sequence and the next stage in its evolution?

  In the core of a star, a proton-proton c vi+9spp +jhf*hain reaction takes place.
$4^1_1​H$→$^4_2​He$+$2^0_{+1}​β^+$+$2\,ν_e$​+$2\,γ$
After the initial stage of the reaction, two positrons annihilate with electrons present in the surroundings. Which of the following correctly shows the nature of the chain reaction and the energy released due to annihilation?

  The parallax angles omv.jjl1c .3k a4y f/pyf Star A and Star B are 0.250 arcseconds and 0.500 arcseconds respectively. What is the shortest possible distance, in parsec, between Star Ajmpcla.f1k4 3y vjy/. and Star B?

  A star with a mass similar to the Sun, a temperatu t,pboqh8 lv 01e1e3rqegzig ,i yf+0)pso;z; re hotter than the Sun, and a radius similar to the Earth would be found in which region of the usual Hertzsprung-Russell bf pl,rq0 ,i1 gspv+o8e egeyz;1t;qio3h)0zdiagram?

  The luminosity of the Sun .nuba.l.d a7 zis $L_⊙$​. A main sequence star with twice the radius of the sun and twice the temperature of the sun has a luminosity of $L$. What is the ratio of $\frac{L}{⊙​L}​$ ?

  Some regions on the H-R diagmhr ya.6 m-bnks(z (4kram are labelled.

A main sequence star with a mass of three times the Sun will evolve through a series of stages. Which of the following sequences of stages could correctly represent the path of the evolution of this star?

  For fusion reactions to occur in a cloud of stellar , fk9;cnww5( ms5 1kwmewtyr8 dust, a combination of high temperature and high density among hydrogen nuclei is essentw9ews1f kycw m5 ;kr mn(8tw,5ial. Which of the following correctly shows why high temperature and high pressure are needed?