We need to directly measure the spectral type in order to determine the surface temperature of a star.
<h3>How do you find the properties of a star?</h3>
Astronomers can determine the temperature of a star by looking at its color and spectrum. The apparent brightness of a star describes how luminous it looks to us. The brightness of a star tells us how bright it really is. The luminance can be determined using both the perceived brightness and the distance.
A star's luminosity, or the total amount of energy it emits each second, is determined by two factors: The stellar photosphere's "Effective Temperature," T. the star's total surface area, which is influenced by its radius, R.
Because it controls how much fuel a star has and how quickly it burns it, a star's mass is its most fundamental characteristic. The majority of a star's life is spent burning hydrogen into helium in its core, which generates energy. The star needs to achieve a balance between gravity and outward pressure in order to continue to be "alive."
To know more about stellar property visit:
brainly.com/question/14950677
#SPJ4
The correct answer is: <span>X, W, Y, Z
In fact, the elastic potential energy of a spring is given by
</span>
![U= \frac{1}{2}kx^2](https://tex.z-dn.net/?f=U%3D%20%5Cfrac%7B1%7D%7B2%7Dkx%5E2%20)
<span>where k is the spring constant and x is the stretching of the spring with respect to its rest position.
In this problem, all the four springs are stretched by the same distance x. This means that their difference in potential energy is due only to the difference between their spring constant: the larger the spring constant, the greater the energy. Therefore we can list the springs from the one with largest spring constant to the one with smallest constant, and this list corresponds to listing the springs from the one with largest energy to the one with smallest energy:
X, W, Y, Z</span>
Answer:
32I
Explanation:
Data provided in the question:
Rotational inertia of a sphere about an axis through the center = I
Now,
Let the radius of the sphere be 'R'
also,
Rotational inertia = MR²
Here,
M is the mass
Mass = Density ÷ Volume
Volume of sphere = ![\frac{4}{3}\pi R^3](https://tex.z-dn.net/?f=%5Cfrac%7B4%7D%7B3%7D%5Cpi%20R%5E3)
Therefore,
M = Density × ![\frac{4}{3}\pi R^3](https://tex.z-dn.net/?f=%5Cfrac%7B4%7D%7B3%7D%5Cpi%20R%5E3)
Thus,
I = ![\text{Density}\times{\frac{4}{3}\pi R^3}\times R^2](https://tex.z-dn.net/?f=%5Ctext%7BDensity%7D%5Ctimes%7B%5Cfrac%7B4%7D%7B3%7D%5Cpi%20R%5E3%7D%5Ctimes%20R%5E2)
Now for the sphere of radius twice the radius i.e 2R
Volume = ![\frac{4}{3}\pi (2R^3)=\frac{4}{3}\pi\times8R^3](https://tex.z-dn.net/?f=%5Cfrac%7B4%7D%7B3%7D%5Cpi%20%282R%5E3%29%3D%5Cfrac%7B4%7D%7B3%7D%5Cpi%5Ctimes8R%5E3)
Since the density is same
Mass = ![\text{Density}\times\frac{4}{3}\pi8R^3](https://tex.z-dn.net/?f=%5Ctext%7BDensity%7D%5Ctimes%5Cfrac%7B4%7D%7B3%7D%5Cpi8R%5E3)
Thus,
I' = ![\text{Density}\times{\frac{4}{3}\pi 8R^3}\times (2R)^2](https://tex.z-dn.net/?f=%5Ctext%7BDensity%7D%5Ctimes%7B%5Cfrac%7B4%7D%7B3%7D%5Cpi%208R%5E3%7D%5Ctimes%20%282R%29%5E2)
or
I' = 8 × 4 × ![\text{Density}\times{\frac{4}{3}\pi R^3}\times R^2](https://tex.z-dn.net/?f=%5Ctext%7BDensity%7D%5Ctimes%7B%5Cfrac%7B4%7D%7B3%7D%5Cpi%20R%5E3%7D%5Ctimes%20R%5E2)
or
I' = 32I
Answer : The change in momentum of an object is equal to the impulse that acts on it.
Explanation :
Change in momentum : The change in momentum of an object is the product of the mass and the change in velocity of an object.
The formula of change in momentum is,
![\Delta p=m\times \Delta v](https://tex.z-dn.net/?f=%5CDelta%20p%3Dm%5Ctimes%20%5CDelta%20v)
Impulse : An impulse of an object is the product of the force applied on an object and the change in time. Impulse is also equivalent to the change in momentum of an object.
![J=F\times \Delta t](https://tex.z-dn.net/?f=J%3DF%5Ctimes%20%5CDelta%20t)
Proof :
![J=F\times \Delta t\\\\J=(m\times a)\times \Delta t\\\\J=m\times (a\times \Delta t)\\\\J=m\times \Delta v=\Delta p](https://tex.z-dn.net/?f=J%3DF%5Ctimes%20%5CDelta%20t%5C%5C%5C%5CJ%3D%28m%5Ctimes%20a%29%5Ctimes%20%5CDelta%20t%5C%5C%5C%5CJ%3Dm%5Ctimes%20%28a%5Ctimes%20%5CDelta%20t%29%5C%5C%5C%5CJ%3Dm%5Ctimes%20%5CDelta%20v%3D%5CDelta%20p)
Hence, the change in momentum of an object is equal to the impulse that acts on it.