Answer:
C) A low-density, cool gas in isolation creates a continuous spectrum.
Explanation:
Kirchhoff’s laws established that:
- A solid, liquid or dense incandescent gas emits a continuous spectrum.
- A hot and diffuse gas produces bright spectral lines (emission lines).
- A gas of lower temperature against a source of continuum spectrum, produces dark spectral lines (absorption lines) superposed in the continuum spectrum.
Stars are perfect examples for Kirchhoff’s laws. Since in the case of the stars, the photons that are received are not directly from the nucleus, but those that have traveled hundreds of thousands of years to reach the stellar atmosphere. Due to the stars are not at homogeneous temperature, density and pressure, but have gradients in different layers because of the nuclear reactions, superficial gravity or to its constant exchange of heat with its surroundings in an attempt to reach the thermodynamic equilibrium, the continuum observed in the stellar spectra comes from the inner layer of the photosphere, while absorption lines are formed in the outer layer of the photosphere and the stellar atmosphere. More accurately, a photon of the inner layer of the photosphere will be absorbed by an electron of an atom or ion that is in the outer layer, generating an electronic transition¹, the electron, upon returning to its base state will emit a photon or a series of photons that will not necessarily go in the same direction of the incident photon, creating an absorption line in the stellar spectrum.
On the other hand, in the case where the stars have surrounding material (diffuse gas), the atoms, molecules or ions in the medium are excited by the radiation that comes from the stellar atmosphere, thus producing an emission spectrum.
Key terms:
¹Electronic transition: When an electron passes from one energy level to another, either for the emission or absorption of a photon.
The answer should be ''Decrease'' to fill in the blank because squirrels usually live in trees and get food from there so without a place to live when its raining and no food to survive, than they would die and lessen their population so that's why decrease is the answer.
m = mass of pellet = 2.10 x 10⁻² kg
x = compression of spring at the time launch = 9.10 x 10⁻² m
h = height gained by the pellet above the initial position = 6.10 m
k = spring constant
using conservation of energy
spring potential energy = gravitational potential energy of pellet
(0.5) k x² = m g h
inserting the values
(0.5) k (9.10 x 10⁻²)² = (2.10 x 10⁻²) (9.8) (6.10)
k = 303.2 N/m
Answer:
temperature of about 2.72548 ± 0.00057 K.
Explanation:
The cosmic background radiation is an electromagnetic radiation that remains from an early stage of the universe during the big bang. It was accidentally discovered in 1965 by two American radio astronomers Arno Penzias and Robert Wilson. The radiation was given off before the formation of stars and planets, when the universe was young, denser, hotter, and filled with a uniform glow from a white-hot fog of hydrogen plasma, which cooled down as the universe expanded. From calculations, it was deduced that the radiation had a temperature of 2.72548±0.00057 K, which is close to the temperature of the universe during its formation.
The most common price control is setting a fixed rent price to protect the tenants. There are other alternatives to this price control. Also, price control should be carefully implemented.
Rent regulation is a term that refers to a set of laws that focus on ensuring that individuals have access to rented housing.
The rental regulation system has a principe that is:
- Price controls: Set a rent price and set the increase in a percentage of it (the rent is $ 100 and the annual increase is 5%)
There are alternatives price control such as:
- Price according to the type of property: Set a rental price according to the type of property and its benefits (for example pool, garage, garden, etc)
- Price according to the number of tenants: Set a rental price according to the number of people who will inhabit the property
Generally, tenants are allowed to raise the value of the rent each year by a minimal proportion. This is necessary to avoid that the landlord does not increase the rental value in large amounts because the tenant will not have access to the rented house.
However, governments should be careful with this regulations because they can negative afect the landlord by limiting his rights over the property.
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