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3 years ago

What do the movements of stars and galaxies tell astronomers about how the universe formed?

1 answer:

3 0

This could be Hubble's law, or something related to it. I think there's a possibly Doppler RED SHIFT in the optical spectra of stars etc as observed on the earth. It seems that they are accelerating away from the earth, and that the further away they are the faster they are moving.
It seems that this has been connected to the idea of "The Big Bang" theory of the origin of the universe which seems to have superceded Professor Sir Fred Hoye's Steady State theory of the universe.
There's some Special Relativity in this lot, too.

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Explain why an object’s weight is dependent upon where in the universe it is located.

strojnjashka [21]

Answer:

The weight of any object will depend on its location in the universe, commanded by the law of gravitacion universal de Newton

Explanation:

Everything obeys the law of universal gravity proposed by Newton. Where the attraction force with which one body attracts another depends on the mass of the body that attracts the body with less mass, the radius of the body with the greatest mass and the universal gravitational constant.

For a better understanding of this concept let us use examples with numeric values. In the first example we will determine with what force planet Earth attracts a person of 70 [kg].

And in the second example we will perform the same exercise but on a planet like Jupiter

Example 1:

A person with a mass of 70 [kg] is located on planet Earth which has a mass of 5.97x10^24 [kg] and a terrestrial radius of 6371 [km]. Find the force exerted by the planet upon the person.

We have the law of universal gravity

$F=G*\frac{m_{1} *m_{2} }{r^{2} } \\where\\G = 6.67*10^-11[\frac{N*m^{2} }{kg^{2}} ]\\m_{1}=70[kg]\\m_{2}=5.97*10^{24} [kg]\\r= 6371[km]$

Now replacing the values in the equation we have:

$F=6.67*10^{-11} *\frac{70*5.97*10^{24} }{(6371*10^3)^{2} } \\F=687[N]$

We can appreciate that if we only use the terms of mass of the earth, the gravitational constant and the radius of the earth, we will have the value of the gravity accelaration of the earth. Let's check

$g_{earth} =6.67*10^{-11} *\frac{5.97*10^{24} }{(6371*10^3)^{2} } \\g_{earth} = 9.81 [m/s^{2} ]$

Example 2:

A person with a mass of 70 [kg] is located on planet Jupiter which has a mass of 1.899x10^27 [kg] and a radius of 71492 [km]. Find the force exerted by the planet upon the person.

$F=6.67*10^{-11}*\frac{70*1.899*10^{27} }{(71492*10^3)^{2} } \\F= 1734.73[N]$

We will calculate the value of the gravity accelaration of Jupiter. Let's check

$g_{jupiter} = 6.67*10^{-11} *\frac{1.899*10^{27} }{(71492*10^3)^{2} } \\g_{jupiter}= 24.8 [m/s^2]\\$

Therefore an object in jupiter will weigh more than 2.5 times its weight than on planet Earth.

We found that the force of attraction or the weight of any object will depend on its location in the universe, commanded by the law of gravitacion universal de Newton

6 0

3 years ago

A boulder on the mythical planet mongo drops off a cliff and falls from rest 1000 m in 10.0 s. (A) what's the initial speed of t

Amiraneli [1.4K]

At rest, initial speed zero

x=v(initial) t+ 1/2 at^2
-1000m=0(10) + 1/2 a 10^2
-1000m=50a
a = -20 m/s^2

6 0

3 years ago

An object that is accelerating may be

pickupchik [31]

The answer of this question is D. All of the above

Acceleration happen when an obeject change its velocity. It has nothing to do with speed.

The huge misconception about acceleration is when we thought it only aply if we increase our speed ( in a sport match, sportcaster often describe acceleration as an increase in players speed)

slower, faster, right , left, it does not matter, as long as that object change its velocity, it accelerates

8 0

3 years ago

You have a horizontal cathode ray tube (CRT) for which the controls have been adjusted such that the electron beam should make a

Dvinal [7]

Answer:

Explanation:

Rotate it slowly to establish whether the spot moves. If it is broken, it will stay as it is. By rotating it the electrons' path to the centre of the screen will be tilted to another position by any external disturbing field.

8 0

3 years ago

As blood passes through the capillary bed in an organ, the capillaries join to form venules (small veins). If the blood speed in

Semenov [28]

Answer:

$A_2 = 2.5\ cm^2$