Someone help me, I'm stuck

The mass luminosity relation L  M 3.5 describes the mathematical relationship between luminosity and mass for main sequence sta

ivanzaharov [21]

Answer:

(a) 11.3 L

(b) 10 M

Explanation:

The mass-luminosity relationship states that:

Luminosity ∝ Mass^3.5

Luminosity = (Constant)(Mass)^3.5

So, in order to find the values of luminosity or mass of different stars, we take the luminosity or mass of sun as reference. Therefore, write the equation for a star and Sun, and divide them to get:

Luminosity of a star/L = (Mass of Star/M)^3.5 ______ eqn(1)

where,

L = Luminosity of Sun

M = mass of Sun

(a)

It is given that:

Mass of Star = 2M

Therefore, eqn (1) implies that:

Luminosity of star/L = (2M/M)^3.5

Luminosity of Star = (2)^3.5 L

Luminosity of Star = 11.3 L

(b)

It is given that:

Luminosity of star = 3160 L

Therefore, eqn (1) implies that:

3160L/L = (Mass of Star/M)^3.5

taking ln on both sides:

ln (3160) = 3.5 ln(Mass of Star/M)

8.0583/3.5 = ln(Mass of Star/M)

Mass of Star/M = e^2.302

Mass of Star = 10 M

3 0

3 years ago

Dalton proposed the first atomic model. Which of these statements accurately reflected his thinking at that time?

Sunny_sXe [5.5K]

B. Atoms are solid balls

3 0

3 years ago

Read 2 more answers

As part of an exercise program, a woman walks south at a speed of 2.00 m/s for 60.0 minutes. She then turns around and walks nor

Anastaziya [24]

Answer:

Option A

Solution:

As per the question:

The distance covered by the woman in the North direction, d = 3000 m

Time taken to travel in North direction, t = 25.0 min = 1500 s

Velocity of woman in the south direction, v = 2.00 m/s

Time taken in the south direction, t' = 60.0 min = 3600 s

Now,

The distance covered in the south direction, d' = vt' = $2.00\times 3600 = 7200\ m$

Now, the total displacement is given by:

D = d' - d = 7200 - 3000 = 4200 m in South

(a) Average velocity of the woman in the whole journey is given by:

$v_{avg} = \frac{Total\ displacement}{Total\ time} = \frac{4200}{t + t'}$

$v_{avg} = \frac{4200}{1500 + 3600} = 0.8235\ m/s$ ≈ 0.824 m/s South

6 0

2 years ago

When forces acting on an object

Ksju [112]

Answer:

it will not change

Explanation:

if the forces are of equal force then there would be no movement because one force was not stronger to move it

6 0

2 years ago

Read 2 more answers

What do the atoms of elements in the same group have in common? A. They have the same atomic numbers. B. They have the same aver

sergiy2304 [10]

Answer:

A. They have the same atomic numbers.

Explanation:

Elements are defined based on the atomic number, which is the number of protons in the nucleus: this means that atoms of the same element have always the same number of protons in their nuclei (and so, always the same atomic number).

The other choices are wrong because:

B. They have the same average atomic masses. --> this is false for isotopes, which are atoms of the same element having a different number of neutrons. Since the atomic mass is calculated from the sum of the masses of protons and neutrons in the nucleus, two isotopes of the same element have different atomic mass

C. They have the same number of electron shells. --> this can be false when an atom of an element loses/gains an electron, becoming an ion: in that case, the number of electron shells can change, since the number of electrons has changed.

D. They have the same number of electrons in their outermost shells. --> this is also false in case one of the atoms is an ion, since the number of electrons is different.

8 0

3 years ago