All categories

3 years ago

How is the size of stars measured?

1 answer:

Ber [7]3 years ago

4 0

Most of the stars in our universe are in binary systems. Hence, the size of the stars can be found when one star eclipses the other. When so happens, the change in the luminosity is measured and size is calculated. Another way is by measuring the luminosity of the star and comparing it with the Sun's luminosity. As the luminosity is dependent on the size of the star, the radius of the star can be calculated when compared to the Sun. Following formula can be used:

Star's radius/Sun's radius = (Sun's temperature/star's temperature)2 Sqrt[star's luminosity/Sun's luminosity].

You might be interested in

An unbalanced force is defined as a force that __________. allows an object to remain at rest cause an object to accelerate in a

fredd [130]

cause an object to accelerate in a direction opposite to the unbalanced force

Explanation:

An unbalanced force is defined as any force that causes an object to accelerate in a direction opposite to the unbalanced force.

The unbalanced force is the net or resultant force describe in newton's second law of motion.

In the first law, it is the external force that causes the motion of a body to change.

Unbalanced forces can cause body to either accelerate in the direction of the force or in an opposite direction of the force.

learn more:

Newton laws brainly.com/question/11411375

#learnwithBrainly

5 0

3 years ago

Read 2 more answers

A concrete slab shown in Figure 5 is being lifted by using three cables connected to the slab at points A, B and C. The slab is

xxMikexx [17]

Answer:

Fad = 28.8 kN

Fbd = 16.4 kN

Fcd = 28.1 kN

Explanation:

First, find the length of each cable.

AD = √((2 m)² + (0.5 m)² + (2.5 m)²)

AD = √10.5 m

AD ≈ 3.24 m

BD = √((1.5 m)² + (1 m)² + (2.5 m)²)

BD = √9.5 m

BD ≈ 3.08 m

CD = √((1 m)² + (1 m)² + (2.5 m)²)

CD = √8.25 m

CD ≈ 2.87 m

Next, use similar triangles to find the x, y, and z components of each tension force.

Fadx = 2/3.24 Fad = 0.617 Fad

Fady = 0.5/3.24 Fad = 0.154 Fad

Fadz = 2.5/3.24 Fad = 0.772 Fad

Fbdx = 1.5/3.08 Fbd = 0.487 Fbd

Fbdy = 1/3.08 Fbd = 0.324 Fbd

Fbdz = 2.5 / 3.08 Fbd = 0.811 Fbd

Fcdx = 1/2.87 Fcd = 0.348 Fcd

Fcdy = 1/2.87 Fcd = 0.348 Fcd

Fcdz = 2.5/2.87 Fcd = 0.870 Fcd

Now sum the forces in the x, y, and z directions:

∑Fx = ma

-0.617 Fad + 0.487 Fbd + 0.348 Fcd = 0

∑Fy = ma

-0.154 Fad − 0.324 Fbd + 0.348 Fcd = 0

∑Fz = ma

60 kN − 0.772 Fad − 0.811 Fbd − 0.870 Fcd = 0

To solve this system of equations algebraically, start by subtracting the first two equations, eliminating Fcd.

-0.463 Fad + 0.811 Fbd = 0

0.811 Fbd = 0.463 Fad

Fbd = 0.571 Fad

Substitute into either of the first two equations:

-0.617 Fad + 0.487 (0.571 Fad) + 0.348 Fcd = 0

-0.617 Fad + 0.278 Fad + 0.348 Fcd = 0

-0.339 Fad + 0.348 Fcd = 0

0.348 Fcd = 0.339 Fad

Fcd = 0.975 Fad

Now substituting into the third equation:

60 kN − 0.772 Fad − 0.811 Fbd − 0.870 Fcd = 0

60 kN − 0.772 Fad − 0.811 (0.571 Fad) − 0.870 (0.975 Fad) = 0

60 kN − 0.772 Fad − 0.463 Fad − 0.849 Fad = 0

60 kN − 2.083 Fad = 0

Fad = 28.8 kN

Solving for the other two tension forces:

Fbd = 0.571 Fad = 16.4 kN

Fcd = 0.975 Fad = 28.1 kN

3 0

3 years ago

Read 2 more answers

Which explanation of the solar system best fits the observations of the planets and how they orbit the sun?Question options:The

diamong [38]

<h2>Answer: The planets formed at the center of a collapsing spinning cloud of gas and dust.</h2>

The most accepted theory so far, in relation to the formation of our solar system is that it was originated by the contraction of a cloud of interstellar gas due to its own gravity.

To understand it better:

According to this theory, a cloud of gas and interstellar dust began to shrink due to its own gravity. This led to the increase in the temperature of the system, which began to rotate forming a large gas sphere in the center (the Sun) with a flat disk around it.

This is how the Sun formed from the sphere in the center and the planets formed from the disk orbiting in the same plane.

6 0

4 years ago

The place kicker on a football team kicks a ball from ground level with an initial speed of 5.80 m/s at an angle of 17.0° above

Likurg_2 [28]

Answer:

0.34 s

Explanation:

Given that,

Initial speed of a ball, u = 5.8 m/s

It is kicked at an angle of 17.0° above the horizontal.

The vertical component of velocity will be,

$u_y=u\sin\theta\\\\=5.8\times \sin 17\\\\=1.69\ m/s$

Let it takes t time in the air before it lands on the ground again. It can calculated as :

$t=\dfrac{2u_y}{g}\\\\t=\dfrac{2\times 1.69}{9.8}\\\\t=0.34\ s$

So, it will take 0.34 seconds.

8 0

3 years ago

A drivers blank affects how likely it is that he or she will take risks behind the wheel.

Sveta_85 [38]

Hello, Ayalaarianna6otpduy!

I believe your answer is Speed!

Glad I Could Help, And Good Luck!

~AnonymousGiantsFan~

4 0

3 years ago