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Isotopes have the same number of protons so they both have 17 and a different amount of neutrons which is why the mass number is different
Answer:
0.0957 g
Explanation:
Half life is the time required by the substance to decay to half of its initial mass. Most often exponential decays of radioactive substances are explained by half life. Half life remains constant throughout the life of decay.
It is given as;
<em> N</em>(t) = N₀ (1/2)^t/t1/2
Where;
<em>N</em>(t) = Amount remaining after certain time
N₀ = The starting initial amount
t1/2 = Half life of given substance
Putting values,
<em> N</em>(t) = 98 × (1/2)^215/21.5
<em> N</em>(t) = 0.0957 g
There are a few ways to do this. The best way I can think of is to start out the paint with no additives and have that as a control. You can test that on whatever your painting or do it in a lab with heat lamps and lights if that is a possible option. However you decide to do the testing, after starting with the control test, add different additives and see which ones fades less the original without any additives. This is the best scenario for a simple yet informative test.
Hope that helps!
The answer: less frequency, causing the pitch to be lowered.
This is known as the Doppler effect. When you have an object that is producing sound while moving, the side that it is moving towards to will have waves that will become a bit more squished together, while the other side that it is moving away from will have waves that are spaced a bit more apart from each other. The only determining factor in this is the magnitude of the speed, so the faster the object is moving towards or away from you, then the more severe pitch change the object will have.
In this case, it's just asking in general what would happen if the horn was moving away from you while it was giving off sound waves. Therefore, since it is moving away from you, its sound waves are a bit further apart, resulting in a lowered frequency and pitch.
<span>Quantum mechanic model is based on mathematics. As per this theory the exact position and momentum of electron is impossible to understand. It uses complex shapes of orbitals called electron clouds. n describes the energy of an electron. Larger the value of n larger the distance of electron from the nucleus and larger the orbital. l describles the shape of orbital. Orbitals having same of value of n and different values for l are called subshells.</span>
