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2 years ago

Which of the following statements is true?

Physics

1 answer:

9966 [12]2 years ago

5 0

Answer:

c) the distance a star is from Earth affects how bright it appears in the night sky.

Explanation:

a) there are MUCH bigger stars in the universe then the sun. The sun is said to be a medium star.

b) If the sun were to burn out it would affect earth a lot. The sun is needed for Earth's survival. Earth needs the heat from the sun or it'd a big cold planet full of ice that probably couldn't support life.

d) the big bang theory supports that the universe is growing

I know c), is correct

You might be interested in

Two astronauts are 2.00 m apart in their spaceship. One speaks to the other. The conversation is transmitted to earth via electr

Eduardwww [97]

Answer:

$D=1693742.7m$

Explanation:

For sound waves we have v=d/t where v is the speed of sound and d the distance between the astronauts, while for electromagnetic waves we have c=D/t where c is the speed of light and D the distance between the spaceship and Earth. <em>We have written both times as the same</em> because is what is imposed by the problem, so we have t=d/v=D/c, which means:

$D=\frac{dc}{v}$

And for our values:

$D=\frac{(2m)(299792458m/s)}{354m/s}=1693742.7m$

5 0

3 years ago

A crate is sliding on the floor. If there is a total force acting on the crate in the same direction as it is sliding, the crate

Leto [7]

But we do not know whether the force is pushing or pulling (the same direction (both forces are parallel) but: .........[ ]<-F-- or .......[ ]--F-->). I suppose the correct answer is B

7 0

3 years ago

During science class, while studying mixtures, you mix together iron filings and sand. Your teacher challenges you to separate t

Lapatulllka [165]

Answer : Use a magnet to pull out the iron filings as they are attracted to a magnet

Explanation : we use the magnet to separate the sand from the iron filing. Because the magnet has an attraction power.

We can say that we can use the magnet to attract the iron filings out of the mixture because iron is magnetic solid, but sand will not attract because sand is not magnetic solid.

So, we use a magnet to pull out the iron filings as they are attracted to a magnet.

8 0

3 years ago

Read 2 more answers

About 65 million years ago an asteroid struck Earth in the area of the Yucatán Peninsula and wiped out the dinosaurs and many ot

9966 [12]

Answer:

$2.44156\times 10^{13}\ m^3$

29010.53917 m

Explanation:

$\rho$ = Density of asteroid = 2 g/cm³

V = Volume

d = Diameter = 10 km

r = Radius = $\dfrac{d}{2}=\dfrac{10}{2}=5\ km$

v = Velocity = 11 km/s

$H_v$ = Heat vaporization of water = $2.26\times 10^6\ J/kg$

$\Delta T$ = Change in temperature = 100-20

Mass is given by

$m=\rho V\\\Rightarrow m=\rho\dfrac{4}{3}\pi r^3\\\Rightarrow m=2000\dfrac{4}{3}\times \pi\times 5000^3\\\Rightarrow m=1.0472\times 10^{15}\ kg$

The kinetic energy is

$K=\dfrac{1}{2}mv^2\\\Rightarrow K=\dfrac{1}{2}1.0472\times 10^{15}\times 11000^2\\\Rightarrow K=6.33556\times 10^{22}\ J$

Heat is given by

$Q=mc\Delta T+mH_v\\\Rightarrow 6.33556\times 10^{22}=m\times (4186\times (100-20)+2.26\times 10^6)\\\Rightarrow m=\dfrac{ 6.33556\times 10^{22}}{4186\times (100-20)+2.26\times 10^6}\\\Rightarrow m=2.44156\times 10^{16}\ kg$

Mass of water is $2.44156\times 10^{16}\ kg$

Volume is $\dfrac{2.44156\times 10^{16}}{10^3}=2.44156\times 10^{13}\ m^3$

Amount of water is $2.44156\times 10^{13}\ m^3$

If it were a cube

$h=V^{\dfrac{1}{3}}\\\Rightarrow h=(2.44156\times 10^{13})^{\dfrac{1}{3}}\\\Rightarrow h=29010.53917\ m$

The height of the water would be 29010.53917 m

4 0

3 years ago

Could dark matter be a higher dimensional object? Why?

REY [17]

Well dark matter is , in a layman terms just a concept used to identify missing mass in the universe. (extremely simplified and probably wrong but look that up). It could be but then if it is then we would still be able to percive the matter in some form. All we know from instruments is that they have mass and absorb light. We would need more info before any conclusions but it is 100% a possibility. But remember that when someone says "3-d" for example they are talking about a certain space.. technically matter exists on all planes (at least all the planes we know of in our local universe.) The laws of the cosmos are not yet proven to be constant and even if they are what of outside it?

When you take high school physics ask your teacher.

3 0

3 years ago