a star converted every bit of its mass into energy the conversion efficiency would be 100%. However, no star is this efficient in its energy production. Stars with less than 1.3 solar masses (most stars are less than 1.3 solar masses) convert hydrogen into helium with an efficiency of only 0.7%. Bearing in mind that the Sun has a mass of 2 × 1030 kg, how long will it live if it converts all of its hydrogen into helium with an efficiency 0.7%? Please note that it won't actually convert all of its hydrogen into helium so this is a rather optimistic upper limit for the lifetime of the Sun. Also, 1 year = 365.25 days.Lifetime = _________ years

Q: Star A and Star B are both on the main sequence. Star A is 74 times more luminous than Star B. What…

A:

Q: The two types of cycles proposed in the stars for fusion are ________ a) p-p cycle and p-e cycle…

A: Option b

Q: All stars start their lives with the same basic composition. What determines their differences? O…

A: Mass they formed with

Q: In a binary star system, the average separation between the stars is 4.0 AU, and their orbital…

A:

Q: A red giant star might have radius = 104 times the solar radius, and luminosity = 1730 times solar…

A: This problem can be solved using Stefan-Boltzmann law of Black body radiation.

Q: A star has a surface temperature of T = 10,000 K and a radius three times that of the Sun, R = 3R…

A:

Q: Let's examine how we know that the Sun cannot power itself by chemical reactions. Using the fact…

A:

Q: Why are metals less abundant in older stars than in younger stars?

A: Answer: The metals which basically are non hydrogen and helium material are produced or created in…

Q: If a star has a surface temperature 2 times lower than the Sun's and a luminosity the same as the…

A: Given, If To is the surface temperature of the sun, Lo is the luminosity of the sun Then for the…

Q: If a star has a radius 2 times larger than the Sun's and a luminosity 1/4th that of the Sun, how…

A: Given that Radius of star, R = 2  luminosity of the star ,

Q: If one star has a temperature of 5,000 K and another star has a temperature of 8,500 , how much more…

A:

Q: The mass-luminosity relation describes the mathematical relationship between luminosity and mass for…

A: L/Lo = (M/Mo )3.5  here the luminosity is to be found in terms of Lo  M = 4Mo

Q: How do the temperature and size of a Sun-sized star fluctuate over the course of its life?…

A: Immediate Assistance : You cannot wait for help if you require quick aid. Because it also implies…

Q: This star has a mass of 3.3 MSun. What is the main sequence lifetime of this star? You may assume…

A:

Q: Which elements are created in stellar nucleosynthesis? (Select all that apply) - oxygen - helium…

A: Among the elements listed, hydrogen and helium were created during big band and the rest of the…

Q: Consider a star of mass M=10 solar masses, composed entirely of fully ionized 12C. Its core…

A:

Q: For each type of stellar explosion, identify its progenitor star

A:

Q: What is the life expectancy of a 2-solar-mass star?

A:

Q: If a star has a surface temperature 3 times higher than the Sun's and a luminosity 324 times larger…

A: Luminosity is defined as the radiant power emitted y a light-emitting object like a star.   Stars…

Q: Calculate the total energy output per second in watts (W) of a star that converts 900 million tonnes…

A: To calculate the energy output per second in watts (W) of a star that converts 900 million tonnes of…

Q: Star B has a temperature that is 5 times higher than Star A. How much more energy per second…

A:

Q: Suppose a star has luminosity 100 times greater than than Sun and a radius 4 times greater than the…

A:

Q: The giant star Betelgeuse has an angular diameter as observed from Earth of about 0.05 arc seconds.…

A: Solution:-

Q: Analysis of the spectrum of a solar–mass star shows a periodic back-and-forth shift of its spectral…

A:

Q: Why massive stars are short lived?

A: A massive star has a shorter life spanthan an average star because of fasterhydrogen fuel…

Q: The mass-luminosity relation describes the mathematical relationship between luminosity and mass for…

A:

Q: A neutron star has a radius of 11.5 km and a mass of about 1.35M Calculate the density of this…

A:

Q: Consider two stars on the main sequence, A and B. Star A has a mass of Мо Star B has a mass of 0.2…

A: Solution attached in the photo

Q: When two stars are in the same star system, they can affect each other’s evolution. Two stars in the…

A: Two stars in the same system might evolve at a different pace, depending on their distances in the…

Q: At what wavelengths do stars of surface temperates 20 000 K, 10 000 K, and 3000 K have their peak…

A:

Q: Consider a star for which the stellar power per unit area at distance 1 AU from the star is 4.5…

A: Intensity at a distance is Radius of star is Note:The Stefan Boltzmann constant is Find:Surface…

Q: A converging lens has a focal length of 36.7 cm. A real object is placed 22.4 cm in front of the…

A:

Q: If the hottest star in the Carina Nebula has a surface temperature of 51,000 K, at what wavelength…

A: Concept: "The Wien's displacement law states that the wavelength carrying maximum energy is…

Q: Consider two stars on the main sequence, A and B. Star A has a mass of 9. Мо Star B has a mass of…

A: Solution attached in the photo

Q: Consider three main sequence stars: Star A is 12000 K, Star B is 6000 K, Star C is 3000 K. What are…

A: Given, Star A = 12000 K temprature  Star B = 6000 K temprature  Star C = 3000 K temprature   So the…

Q: Consider an M-dwarf star of mass 0.1M⊙ and luminosity 10−3L⊙. When the star joins the main sequence…

A: Luminosity of the star is defined as the power emitted by the star. Power is simply the energy…

Q: What is the mass of a star with a main-sequence lifetime of 4 billion years? 17 X solar masses

A: According to stellar theories & observations the average lifetime of main-sequence stars has…

Q: Iron is unique among the elements in terms of its nuclear properties, and this gives it a decisive…

A: Explanation: Iron is not the heaviest element that stars can produce, just the heaviest one that can…

Q: .

A:

Q: Why do metal-poor stars have a wider range of orbital shapes than metal-rich stars like the sun?

A: Stars are classified into two categories. Population I and Population II.   Population I stars are…

Q: If a star converted every bit of its mass into energy the conversion efficiency would be 100%.…

A:

Q: Calculate the surface temperature of the star (in K), if the radius of the star is 4,3x10° m and the…

A: Given :               radius of star R = 4.3 x 108 m            mass lost per second = 26 x 1010 kg…

Q: There are 200000 AU radius clouds will form a star of 10 solar masses and the 150000 AU radius…

A:

Q: Let's calculate how much mass will be lost by the Sun during the course of its main-sequence…

A: Given The total mass of the Sun   msun                                       =  2 × 1030 kg Earth…

Q: The Sun has a mass of 1.989 × 10^30 [kg], but only 10% of that mass is available for hydrogen fusion…

A:

Stellar evolution

We may see thousands of stars in the dark sky. Our universe consists of billions of stars. Stars may appear tiny to us but they are huge balls of gasses. Sun is a star of average size. Some stars are even a thousand times larger than the sun. The stars do not exist forever they have a certain lifetime. The life span of the sun is about 10 billion years. The star undergoes various changes during its lifetime, this process is called stellar evolution. The structure of the sun-like star is shown below.

Red Shift

It is an astronomical phenomenon. In this phenomenon, increase in wavelength with corresponding decrease in photon energy and frequency of radiation of light. It is the displacement of spectrum of any kind of astronomical object to the longer wavelengths (red) side.