00:01
So for this question we are looking at how matter absorb radiation.
00:08
And the radiation is measured in terms of dose, right? dose is the units is grace, where actually grace refers to the jove per kilogram, right, in terms of acid units, energy per unit mass.
00:29
And so we need the meat.
00:32
In our case which is 0 .3 kj for the first part right part a 2 .3 kg of meat and we wanted to absorb 2 ,000 grades of dose.
00:48
Now remember those is energy per unit mass right so to get the total energy required we simply multiply the dose by the mass right 0 .30 and we get 600 joules.
01:08
So this is the energy required.
01:10
Now we know that our photons, our photon energy is 100 kav, but we have to convert it to jose to make the comparison, right, in order to work with the energy that we calculated before, which is in joules.
01:30
So we convert to kiv, for two joules, we multiply by 1 .6, 0 ,000.
01:40
10 to power minus 19.
01:45
We get 1 .60 times 10 to power of minus 14 juice.
01:53
And then now we can calculate the number of photons required simply by dividing total energy required divided by the energy per photon...