<span>In chemistry and physics, the atomic theory explains how our understanding of the atom has changed over time. Atoms were once thought to be the smallest pieces of matter. The first idea of the atom came from the Greek philosopher Democritus. Hope I helped!!</span>

6 0

3 years ago

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If the distance of a galaxy is 2,000 Mpc, how many years back into the past are we looking when we observe this galaxy

ruslelena [56]

The age of the galaxy when we look back is 13.97 billion years.

The given parameters:

<em>distance of the galaxy, x = 2,000 Mpc</em>

According Hubble's law the age of the universe is calculated as follows;

v = H₀x

where;

H₀ = 70 km/s/Mpc

$T = \frac{x}{V} \\\\T = \frac{x}{xH_0} \\\\T = \frac{1}{H_0} \\\\T = \frac{1}{70 \ km/s/Mpc} \\\\T = \frac{1 \ sec}{70 \times 3.24 \times 10^{-20} } \\\\T = 4.41 \times 10^{17} \ sec\\\\T = \frac{4.41 \times 10^{17} \ sec\ \times \ years}{3600 \ s \ \times\ 24\ h\ \times \ 365.25 \ days} \\\\T = 1.397 \times 10^{10} \ years\\\\T = 13.97 \ billion \ years$

Thus, the age of the galaxy when we look back is 13.97 billion years.

Learn more about Hubble's law here: brainly.com/question/19819028

8 0

2 years ago

4. Is the force of the earth’s gravity on the sun stronger, weaker, or the same as the force of the sun’s gravity on the earth?

Nady [450]

Answer:

The first statement is false, the Sun has a stronger gravitational pull.

5 0

3 years ago

This diagram represents the synthesis of nitrogen monoxide. Write a balanced equation of this chemical reaction. A) N2(g) + O2(g

ruslelena [56]

The only balanced equation is B.

If you look at the equation and break it down you can see that in:

$N_{2} + O_{2}$ → $2NO$

Starting from the left side of the equation there are 2 Nitrogen atoms, and 2 oxygen atoms as indicated by the subscript.

To balance the equation, the number of atoms of each element in the right side equation should be equal to left. By putting the numerical coefficient of 2, you will distribute that to each element. So you will end up with 2 nitrogen atoms and 2 oxygen atoms on the left side of the equation. Thus, the equation is balanced.

The answer again, is B.

4 0

3 years ago

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