All categories

3 years ago

Plz help me and I will give u a brainliest in return

Physics

2 answers:

GalinKa [24]3 years ago

7 0

A galaxy is a system of millions or billions of stars, together with gas and dust, held together by gravitational attraction.

There are 100 billion galaxies

The Sun is just one of those 200 billion to 400 billion stars

vladimir1956 [14]3 years ago

4 0

A galaxy is a system of millions to billions of stars, and is held together by gravitational attraction. There are around 2 trillion galaxies.

You might be interested in

What molecular geometry would be expected for f2 and hf?

Kaylis [27]

The molecular geometry of both F2 and HF is linear.

There are only two atoms which are covalently bonded and thus, the bonding scheme with the atoms looks like this;

F --- F

H---F

So, both are linear.

4 0

2 years ago

This type of radiation is smallest and highest in energy: ____ ___.

madreJ [45]

Gamma rays have the highest energies and the shortest wavelengths.

5 0

3 years ago

Read 2 more answers

A rocket in deep space has an empty mass of 150 kg and exhausts the hot gases of burned fuel at 2500 m/s. It is loaded with 600

3241004551 [841]

Answer:

$v(10\,s) \approx 775.387\,\frac{m}{s}$

$v(20\,s)\approx 1905.350\,\frac{m}{s}$

$v(30\,s) \approx 4023.595\,\frac{m}{s}$

Explanation:

The speed of the rocket is given the Tsiolkovsky's differential equation, whose solution is:

$v (t) = v_{o} - v_{ex}\cdot \ln \frac{m}{m_{o}}$

Where:

$v_{o}$ - Initial speed of the rocket, in m/s.

$v_{ex}$ - Exhaust gas speed, in m/s.

$m_{o}$ - Initial total mass of the rocket, in kg.

$m$ - Current total mass of the rocket, in kg.

Let assume that fuel is burned linearly. So that,

$m(t) = m_{o} + r\cdot t$

The initial total mass of the rocket is:

$m_{o} = 750\,kg$

The fuel consumption rate is:

$r = -\frac{600\,kg}{30\,s}$

$r = -20\,\frac{kg}{s}$

The function for the current total mass of the rocket is:

$m(t) = 750\,kg - (20\,\frac{kg}{s} )\cdot t$

The speed function of the rocket is:

$v(t) = - 2500\,\frac{m}{s}\cdot \ln \frac{750\,kg -(20\,\frac{kg}{s} )\cdot t}{750\,kg}$

The speed of the rocket at given instants are:

$v(10\,s) \approx 775.387\,\frac{m}{s}$

$v(20\,s)\approx 1905.350\,\frac{m}{s}$

$v(30\,s) \approx 4023.595\,\frac{m}{s}$

7 0

3 years ago

Why are solids good at transferring heat through conduction?

seraphim [82]

The chemical bonds alow it to pass to the other object.

6 0

3 years ago

Read 2 more answers

A room is heated as a result of solar radiation coming in through the windows. Is this a heat or work interaction for the room?

taurus [48]

Answer:

who r u? I am u. i am me. no sir, you are you. wait idk.

3 0

3 years ago