Answer:
As you may know, each element has a "fixed" number of protons and electrons.
These electrons live in elliptical orbits around the nucleus, called valence levels or energy levels.
We know that as further away are the orbits from the nucleus, the more energy has the electrons in it. (And those energies are fixed)
Now, when an electron jumps from a level to another, there is also a jump in energy, and that jump depends only on the levels, then the jump in energy is fixed.
Particularly, when an electron jumps from a more energetic level to a less energetic one, that change in energy must be compensated in some way, and that way is by radiating a photon whose energy is exactly the same as the energy of the jump.
And the energy of a photon is related to the wavelength of the photon, then we can conclude that for a given element, the possible jumps of energy levels are known, meaning that the possible "jumps in energy" are known, which means that the wavelengths of the radiated photons also are known. Then by looking at the colors of the bands (whose depend on the wavelength of the radiated photons) we can know almost exactly what elements are radiating them.
Answer: V = 3.4 L
Explanation: Use Boyle's Law to find the new volume. P1V1 = P2V2, derive for V2, then the formula will be V2= P1V1 / P2
V2 = 2.5 atm ( 4.5 L ) / 3.3 atm
= 3.4 L
<h2>
Answer:50
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Explanation:
Let
be the airspeed.
Let
be the cross wind speed.
We know that,ground speed is the vector sum of airspeed and cross wind speed and airspeed is perpendicular to cross wind speed.
If
and
are two perpendicular vectors,the resultant vector has the magnitude 
Given,

So,the ground speed is 
If the gymnast mass were doubled, her height (h) from the top of the board would be as follows,
с Stay the same
Explanation:
- The Mass of an object or body does not affect the acceleration due to gravity in any kind of way.
- Light weight objects accelerate more slowly than the heavy objects because when the forces other than the gravity also plays a major role.
- Mass increases of a body when an object has higher velocity or the speed.
- The greater the force of gravity, it would give a direct impact on the object's acceleration; thus considering only a force, the heavier the object is, it would accelerate faster. But an acceleration depends upon the two factors which are force and mass.
- Newton's second law of motion states that the acceleration of an object is dependent upon the two factors which are, the net force of an object and the mass of the object.