00:01
Okay, so this problem want us to determine the number of tissue 137 atoms that would be present in one kilogram of tissue if the equivalent dose in one week is 3 .5c volts.
00:23
So we can determine that using this formula.
00:27
The number of cession 137 atoms that decay in one week is equals to the product.
00:35
Of the decay constant, the number of 617 atoms that is present, which is what we're looking for, n the elapsed time.
00:49
Then we can see that n is equals to this.
00:53
Note that the decay constant is equals to ln of 2 over the half -life.
01:00
We are given the half -life of 617, which is 30 .07 years.
01:06
Then our equation to determine the number of tisham -137 % percent is equal to this.
01:18
Now, to solve this problem, we have to determine the value of the number of tisham -1 -37 atoms that decay in one week.
01:30
So we can determine that from the formula for absorbed dose.
01:40
So absorbed dose is equals to the energy deposited per unit mass by definition.
01:47
Total energy over the mass.
01:51
The total energy here is the product of the number of three seven atoms that decay and the energy per each decay over the mass.
02:07
And the absorbed dose is related to equivalent dose by this formula.
02:14
So the equivalent dose is equals to the product of the absorbed dose and the radiation voting factor.
02:24
So in this case, the equivalent dose is due to the gamma in electrons...