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2 years ago

What is the order of magnitude of the distance of Sun to nearest star in meters?

Physics

2 answers:

Brilliant_brown [7]2 years ago

6 0

Answer:

Mercury, 46,001,272 km from the sun at the nearest point.

Explanation:

neonofarm [45]2 years ago

4 0

Answer:

Approximating the Milky Way as a disk and using the density in the solar neighborhood, there are about 100 billion stars in the Milky Way.

Explanation:

Since we are making an order of magnitude estimate, we will make a series of simplifying assumptions to get an answer that is roughly right.

Let's model the Milky Way galaxy as a disk.

The volume of a disk is:

⋅

Plugging in our numbers (and assuming that

≈

)

⋅

(

)

⋅

(

)

Is the approximate volume of the Milky Way.

Now, all we need to do is find how many stars per cubic meter (

) are in the Milky Way and we can find the total number of stars.

Let's look at the neighborhood around the Sun. We know that in a sphere with a radius of

m there is exactly one star (the Sun), after that you hit other stars. We can use that to estimate a rough density for the Milky Way.

Using the volume of a sphere

(

)

256

−

stars /

Going back to the density equation:

Plugging in the density of the solar neighborhood and the volume of the Milky Way:

(

256

−

)

⋅

(

)

256

stars (or 100 billion stars)

Is this reasonable? Other estimates say that there are are 100-400 billion stars in the Milky Way. This is exactly what we found.

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How many valence electrons does each atom of arsenic (As) have? Arsenic is element 33. It is in period 4 and family 15 (5A or th

vodka [1.7K]

Answer:

It have 5 valence electrons

7 0

3 years ago

Read 2 more answers

. If a pendulum-driven clock gains 5.00 s/day, what fractional change in pendulum length must be made for it to keep perfect tim

inn [45]

Answer:

The appropriate response will be "Length must be increased by 0.012%".

Explanation:

The given values is:

ΔT = 5 s/day

Now,

⇒ $\frac{\Delta T}{T} =\frac{5}{24\times 60\times 60}$

On multiplying both sides by "100", we get

⇒ $\frac{\Delta T}{T}\times 100 =\frac{500}{24\times 60\times 60}$

⇒ $\frac{\Delta T}{T}\times 100=0.005787$ (%)

∵ $T=2\pi\sqrt{\frac{l}{g} }$

On substituting the values, we get

⇒ $\frac{\Delta T}{T}$ % = $\frac{1}{2}\times \frac{\Delta l}{l}$ %

On applying cross multiplication, we get

⇒ $\frac{\Delta l}{l}$ % = $2\times \frac{\Delta T}{T}$ %

⇒ = $2\times 0.05787$

⇒ = $0.011574$

⇒ = $0.012$ %

6 0

3 years ago

Earth is about 150 million kilometers from the Sun, and the apparent brightness of the Sun in our sky is about 1300 watts/m2. Us

nalin [4]

Answer:

$13 W/m^2$

Explanation:

The apparent brightness follows an inverse square law, therefore we can write:

$I \propto \frac{1}{r^2}$

where I is the apparent brightness and r is the distance from the Sun.

We can also rewrite the law as

$\frac{I_2}{I_1}=\frac{r_1^2}{r_2^2}$ (1)

where in this problem, we have:

$I_1 = 1300 W/m^2$ apparent brightness at a distance $r_1$ , where

$r_1 = 150$ million km

We want to estimate the apparent brightness at $r_2$ , where $r_2$ is ten times $r_1$ , so

$r_2 = 10 r_1$

Re-arranging eq.(1), we find $I_2$ :

$I_2 = \frac{r_1^2}{r_2^2}I_1 = \frac{r_1^2}{(10r_1)^2}(1300)=\frac{1}{100}(1300)=13 W/m^2$

5 0

3 years ago

Crystalline salts such as cesium bromide form _____ bonds with _______.

olasank [31]

Ionic bonds with electrostatic attractions

4 0

3 years ago

Read 2 more answers

A pendulum has 711 J of potential energy at the highest point of its swing. How much kinetic energy will it have at the bottom o

Anika [276]

According to law of conservation of energy,
Energy can neither be constructed nor be destroyed but can be transformed from one form to another.

At the highest point of the pendulum(point b), pendulum is associated with potential energy only and no kinetic energy.
Therefore total energy at point b = potential energy = 711 J.... i

At the bottom most point(point a), pendulum is associated only with kinetic energy and no potential energy.
Therefore total energy at point a = kinetic energy ---- ii
From i and ii,
Kinetic energy = potential energy = 711 J.(Conserving energy)

Hence kinetic energy at the bottom most point is 711 J.
Hope this helps!!

7 0

2 years ago