<h2>
Answer: The half-life of beryllium-15 is 400 times greater than the half-life of beryllium-13.</h2>
Explanation:
The half-life of a radioactive isotope refers to its decay period, which is the average lifetime of an atom before it disintegrates.
In this case, we are given the half life of two elements:
beryllium-13:
beryllium-15:
As we can see, the half-life of beryllium-15 is greater than the half-life of beryllium-13, but how great?
We can find it out by the following expression:
Where is the amount we want to find:
Finally:
Therefore:
The half-life of beryllium-15 is <u>400 times greater than</u> the half-life of beryllium-13.
<span>A very rare type of lightning that appears as a reddish-colored sphere is called </span>A + Ball Lightening
The initial kinetic energy of the cart is
After the block is dropped into the cart, if there are no other forces acting on it, the kinetic energy of the new system cart+block must be conserved, so it should be the same as before. But the new mass will be M+m, where m=50kg is the mass of the block. Therefore we can write
from which we find
Fission. Fusion is the reacton that occurs in the Sun. Man has not managed to produce and use the nuclear fusion to a degree and under conditions that permit its use for generating energy to supply electriicity but it is more powerful an efficient than fission.