Calculate the critical density of our universe.
Q: What is the evidence that dark matter exists?
A:
Q: Calculate the age of the universe if the Hubble constant were 65 km/s/Mpc.
A:
Q: Which factor has slowed down the expansion of the universe?
A: The expansion of the universe has slowed down because the object pull each other towards themselves…
Q: Why is dark matter a problem?
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A: Average density of the matter in the universe ρavg=M43πd23=6Mπd2
Q: What is the densest substance in the universe?
A: Osmium is the densest thing in the universe.
Q: Is antimatter, dark matter, dark energy, and degenerate matter all t
A: Antimatter, dark matter ,dark energy and degenerate matter are not all the same thin. Antimatter:…
Q: An 800 nm spectral line when observed from a galaxy is shifted to 920 nm. Calculate the redshift.
A: Redshift is the process by which light from moving sources is shifted to longer wavelengths.…
Q: What is the difference between hot dark matter and cold dark matter? What difference does that make…
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Q: Is there a way to quantify Dark Matter?
A: Required : Is there a way to quantify Dark Matter ?
Q: Is there any difference between antimatter, dark-matter, dark energy and degenerate matter?
A: Antimatter: It is like a simple matter. It also reflects the light. For example, positron is the…
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A: Astronomers estimated that the age of universe is about 12 to 14 billion years. There are two…
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Q: Calculate the age of the universe when its temperature was 10¹¹ K.
A: The universe was once part of a singularity of very high density and temperature. All the forces and…
Q: What is the densest subsatnce in the universe?
A: At a modest temperature and pressure the most densest element on Earth surface is Osmium.
Q: Suppose that we were to discover that all galaxies are actually twice as far away as we think. How…
A:
Q: Calculate the age of the universe for the following Hubble's constant, (b) 65 km/s/Mpc
A: As per Hubble's law, the universe is expanding. If we assume that the expansion's apparent velocity…
Q: Is there a way to quantify Dark Matter?
A: Required : Is there a way to quantify Dark Matter.
Q: How do we measure Dark Matter?
A: Two methods were used by DES scientists to measure dark matter. Firstly, maps of galaxy positions as…
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A: dark matter is the approximate 85% part of the universe. it affects the movement of the celestial…
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A: first option is correct
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A: The critical density for the Universe is given by, ρ = 3H28πG where H is the Hubble constant and G…
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A: Given: The photons can no longer disassociate deuterons.
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A: To find: Evidence that much of the mass of the universe consist of dark energy has come from
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A: Given: kT=mc2
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Q: The Analysis of the Big Bang Theory.
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A: Redshift: It is stated as the change in the frequency of the light and is used to study the position…
Q: Calculate the age of the universe for the following Hubble's constant, m (c) 80 km/s/Mpc Of
A:
Q: Calculate the age of the universe when the temperature was 10¹ K.
A: The age of the universe when the temperature was 1013 K. Given, TemperatureT=1013 K
Q: how big is the universe in numbers
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A: Given: To explain universe is not older than the Hubble time as,
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A: In universe there are millions of stars. These stars are always moving towards Earth or away from…
Q: If the universe had a density equal to its estimated critical density of 9= 10-30 g/cm3, and if it…
A: Given Critical density ρc = 9×10-30 g/cm3 Mass (M) = 2.0 × 1030 kg
- Our universe is expanding and critical density is defined as the average density of matter that is required for the universe to stop this expansion. When the critical density is reached the universe is said to be flat.
- Critical density is given by,
Here H is the Hubble constant and G is Newton’s gravitational constant.
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