<span>The chemical formula for the unknown gas is Ne.
Since we're looking for the rate at which a gas escapes through a small hole, we're dealing with effusion. For effusion, the rate is proportional to the velocity of the gas particles.
Kinetic energy
E = 0.5 mv^2
Since the kinetic energy of individual gas particles is the same if their temperatures are the same, we can create the following equality:
0.5 m1(v1)^2 = 0.5 m2(v2)^2
Double each side to make it simplier.
m1(v1)^2 = m2(v2)^2
Divide both sides by m1 and by (v2)^2, giving
(v1)^2/(v2^2) = m2/m1
And take the square root, giving
(v1)/(v2) = sqrt(m2/m1)
Now let's use the value 1 and the atomic weight of Kr for v1 and m1
1/(v2) = sqrt(m2/83.798)
And for v2, we'll use the value 2.04
1/2.04 = sqrt(m2/83.798)
Now solve for m2.
1/2.04 = sqrt(m2/83.798)
1/4.1616 = m2/83.798
83.798/4.1616 = m2
20.13600538 = m2
So the atomic weight of the unknown gas should be close to 20.136. Looking at a periodic table, I find that neon has an atomic weight of 20.18 which is quite close. Additionally, since neon is a noble gas, its gas particles consist of individual atoms. So the unknown gas is neon.</span>
E. Galaxy Cluster
Explanation:
A galaxy cluster, or cluster of galaxies, is a structure that consists of anywhere from hundreds to thousands of galaxies that are bound together by mutual gravity.
A megaparsec is a million parsecs and there are about 3.3 light years in a mega-parsec. Parsec is rather a natural distance unit for astronomers. The standard abbreviation of a mega-parsec is Mpc.
A parsec is approximately 3.09 x 1016 meters, a megaparsec is about 3.09 x 1022 meters.
Hence, 8 megaparsecs is gigantic size and that can be only of a galaxy cluster consisting of hundreds and thousands of galaxies bounded together.
Keywords: galaxies, parsec, megaparsec, galaxy cluster
Learn more about galaxy clusters and astronomical units from:
https://brainly.in/question/4624292
brainly.com/question/14214806
brainly.com/question/13315988
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<h2>5.3 km</h2>
Explanation:
This question involves continuous displacement in various directions. When it becomes difficult to imagine, vector analysis becomes handy.
Let us denote each of the individual displacements by a vector. Consider the unit vectors
as the unit vectors in the direction of East and North respectively.
By simple calculations, we can derive the unit vectors
in the directions North,
South of West and
North of West respectively.
So Total displacement vector = Sum of individual displacement vectors.
Displacement vector = 
Magnitude of Displacement = 
∴ Total displacement = 
Answer:
a) 
b) 2.36 cm
Explanation:
a) The horizontal distance = x = 6 cm
1 cm = 0.01 m
6 cm = 6 cm * 0.01 m/cm = 0.6 m
Therefore the time taken (t) by the electron to travel from the emission point to the screen can be gotten from:
x = t * 


b) The vertical distance (y) traveled by the electon before it hits the screen is given by:

That statement is FALSE
the scale that calibrated to read from 0 to 500 is usually the standard used by the new kind of service
the older one usually only take up to 340
hope this helps