If a certain star is 4 times as hot as the sun and is 10000 times brighter than the sun, calculate the radius of the star.

Q: Which of the following statements about stellar parallax is true? A. We observe all stars to exhibit…

A: Parallax measurement is used to find the distance of any object from the Geocentric parallax and…

Q: How many times brighter or fainter would a star appear if it were moved to: a. twice its present…

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Q: Two stars of the same diameter or observed to have surface temperatures of 4000 Kelvin and 16,000…

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Q: Before the era of photography, telescopic measurements of star positions (coordinates) in the sky…

A: The first person to succeed at measuring the distance to a star using parallax was F.W. Bessel, who…

Q: If the parallax angle of a star is 0.5", what is the star's distance in light years and kilometers?

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

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Q: Consider two identical stars, A and B. Star B is 10 times farther away than star A. What is the…

A: Two identical stars A and B are given which are at different distances.

Q: High AO BO Co OD OE FO Low High Temperature Low Use the graph above to answer the question. Which…

A: Horizontal axis represents temperature from high to low Vertical axis represents brightness from low…

Q: What is the distance in light years from Earth to a star that makes a parallax angle of 2.0 arc…

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Q: A star is observed to have a parallax of 0.05". If we were to send a radio signal towards this star…

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Q: If the parallax angle of a star is (0.369) arcseconds, then the distance of the star from the Earth…

A: Using the relationship between the parallax angle and distance of the star and the earth is given…

Q: Why can’t astronomers use parallax to measure the distance to stars that are extremely far away?

A: Because it is difficult to measure from earth reason is effects of earth atmospheric. Parallel angle…

Q: The velocities of the two stars are 28km/s and 13km/s, and their periods are both 16 years. Find the…

A: Formula Let period of a star is T, velocity is v, orbital radius is r and , mass is M, Now the…

Q: The satellite Hipparcos was launched in 1989 to measure very accurate parallax angles of stars; it…

A: Parallax is a displacement of an object when it viewed along two different line of sight. Parallax…

Q: If a star has a parallax of 0.025 arc second and an apparent magnitude of 5.0, how far away is it,…

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Q: Calculate the distance of a star if the stellar spectrum indicates an absolute magnitude of -10.0,…

A: The expression for the distance can be written as m-M=5logd10…

Q: the parallax angle of a star to be 0.002 arc-seconds.  what would the  distance be to this star?

A: Given, Parallax angle, p=0.002 arc-seconds

Q: Suppose a star has a luminosity of 7.0x1026 watts and an apparent brightness of 4.0×10-12 watt/m?.…

A: Luminosity of star (L) = 7×1026 watt Apparent brightness (AB) = 4×10-12 Wm2

Q: The apparent magnitude of a star is (4.3) and the parallax angle is (0.161) arcseconds. The absolute…

A: The absolute magnitude of a star is given by the formula, M=m-5 log10D10 where D is distance of the…

Q: Two stars have the difference between their apparent magnitudes +5, so their apparent luminosity…

A: The difference between the apparent magnitude is given as m1-m2=+5

Q: Mention a method to measure temperature of a star.

A: Temperature of the stars cannot be measured directly as they are very far.

Q: If a star is 30 parsecs away what is it's observed parallax shift ?

A: Given thatThe distance to the star (d)=30 parsecsParallax Formulad=1pp=the parallax angle of the…

Q: What is the dependence of the intensities of stars on parallax? Hint: consider the inverse-square…

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Q: is

A: The relationship between apparent visual magnitude(m), Absolute visual magnitude(Mv) and distance(d)…

Q: The apparent magnitude of a star is (4.3) and the parallax angle is (0.161) arcseconds. The absolute…

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Q: ou observe a star with a telescope over the course of a year. You find that this star has a flux…

A: .In vertical direction:psinθ=40sin60Psinθ=4032Psinθ=34.6410 free body diagram:

Q: What did you calculate for the radius of the star that had a temperature of 5880 degrees Kelvin and…

A: Given : Temperature=T=5880∘ K Luminosity=L=78 W We have to calculate the value of radius R of the…

Q: Stars A and B both have the same spectral class. Star A is 7 times farther away than star B. The…

A: Consider the brightness of the stars A and B be FA and FB, respectively, these luminosities be LA…

Q: If light from one star is 1,600 times brighter (has 1,600 times more flux) than light from another…

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Q: If a star has a radial velocity of 25 km/sec and a transverse velocity of 60 km/sec what is the…

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Q: How do you calculate the mass of a star?

A: To calculate mass of a single star is a difficult process however to calculate the mass of binary…

Q: You measure a star to have a parallax angle of 0.12 arc-seconds What is the distance to this star in…

A: Write the given values of the problem- Parallax angle=0.12 arc-second

Q: Over the course of 6 months, a star's parallax angle is measured to be 0.083 arcseconds. What is the…

A: Given that, Parallax angle = 0.083 arcseconds

Q: The Hertzsprung-Russell diagram shows that for most stars, as the absolute magnitude increases, the…

A: Introduction: A star`s composition, structure and temperature changes during its lifetime. Ejnar…

Q: Calculate the distance of a star if the stellar spectrum indicates and absolute magnitude of -10 and…

A: The given data are listed below with suitable variables. Here, M denotes the absolute magnitude and…

Q: Which star is more luminous? (you only have one try for this problem) A) A star with absolute…

A: The absolute magnitude is a measure of the star's luminosity and it is defined as: Luminosity (L) =…

Q: Suppose a star has a luminosity of 7.0x1026 watts and an apparent brightness of 4.0x10-12 watt/m?.…

A: Given: The luminosity is 7x1026 W. The apparent brightness is 4x10-12 W/m2.

Q: How many times hotter than our sun is the hottest type O star, which has a surface temperature…

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Q: Star A is located four times farther from Earth than Star B, but both have the same apparent visual…

A: Questions based on the  star apparent and absolute visual magnitude.

Q: Size, surface temperature, and distance from the Earth are three things that determine the of the…

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Q: If one star has a temperature of 5600 K and another star has a temperature of 8000 K, how much more…

A: Given data The temperature of one star is given as T1 = 5600 K The temperature of another star is…

Q: If a star’s parallax is 35 arcseconds,  what is the distance to the star?

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Q: What types of observations are necessary to determine the motion of a star through space?

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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.