<u>Answer:</u> The energy released in the decay process is
<u>Explanation:</u>
The equation for the alpha decay of Ra-226 follows:
To calculate the mass defect, we use the equation:
Mass defect = Sum of mass of product - Sum of mass of reactant
We know that:
Putting values in above equation, we get:
(Conversion factor: 1 kg = 1000 g )
To calculate the energy released, we use Einstein equation, which is:
Hence, the energy released in the decay process is
The correct answer to
the question that is stated above is the fourth option which is :<span>Blue star.
Blue stars are uncommon but very bright. It has an average luminosity of </span>1,400,000 ( the Sun =1) with a strong UV continuum. The blue stars average mass is 60 ( the Sun =1) and its average radius is 15 <span>( the Sun =1).</span><span>
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<span>In order to calculate an average, we should sum all numbers and divide them by quantity.
Let’s work with qualifications first. Let’s say you got a 10 in 1 exam, then an 8 in 2 exams and a 4 in 2 exams. Your average will be:
= (10*1+8*2+4*2) / 5 = 6.8
If 6 is the minimum, you will pass.
There is another way to calculate this average: applying distributive property.
= 10*1/5+8*2/5+4*2/5 = 6.8
Remember you can convert the fractions into equivalent fractions: 1/5 = 20/100; 2/5 = 40/100
= 10*20/100+8*20/100+4*20/100 = 6.8
We actually don’t have the number of atoms of each mass… we have the percentage instead! So we need to learn this last method for atoms.
Let’s go back to our atoms problem:
73.71 % of atoms have a mass of 27.98 u
14.93 % of atoms have a mass of 28.98 u
11.36 % of atoms have a mass of 29.97 u
So let’s put that in the formula:
Average mass = 27.98 u*73.71 /100 + 28.98 u*14.93 /100 + 29.97u*11.36 /100
So what you have to know is that a percentage can be converted into a fraction, and you should work that fraction in order to find the average. We can make the calculus shorter putting 100 as the common denominator:
Average mass = (27.98 u*73.71 + 28.98 u*14.93 + 29.97u*11.36)/100
So actually we are taking the percentage as if it was the quantity, and 100 as if it was the total (the total of all percentages is always 100). Maybe we don’t have 100 atoms, but it will be the same proportion anyway, whatever number we have! And here it is the result:
Average mass = 28,36u
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Answer:
Prob. D
Explanation:
I am also a Visual Learner.