Answer:
Energy of scattered photon is 232.27 keV.
Kinetic energy of recoil electron is 497.73 keV.
The recoil angle of electron is 13.40°
Explanation:
The energy of scattered photon is given by the relation :
.....(1)
Here E₁ is the energy of incident photon, E₂ is the energy of scattered photon,
is mass of electron and θ is scattered angle.
Substitute 730 keV for E₁, 511 keV for
and 120° for θ in equation (1).

E₂ = 232.27 keV
Kinetic energy of recoil electron is given by the relation :
K.E. = E₁ - E₂ = (730 - 232.27 ) keV = 497.73 keV
The recoil angle of electron is given by :

Substitute the suitable values in above equation.


= 13.40°
The formula for half-life is:

Where A is the amount of iodine-131 initially and after 40 days, t is time, h is half-life of the isotope. Let's plug in our values to the equation:

Therefore, the patient has 0.625 grams of iodine-131 after 40 days.
Answer: 1.8 g
Explanation:
We start first, by calculating the amount of Helium
n = m/M
m = mass of Helium
M = molar mass if Helium
n = 2/4 = 0.5 moles
proceeding further, we use ideal gas law. PV = nRT
Then we have
P1V1/n1T1 = P2V2/n2T2
So that,
n2 = n1T1P2V2/P1V1T2
From the question, we know that, P1 = P2, and T1 = T2. So that,
n2 = n1v2/v1
n2 = (0.5 * 3.9) / 2
n2 = 1.95/2
n2 = 0.975 moles. With this, we can determine the mass, m2 of Helium
n = m/M
m = n * M
m = 0.975 * 3.9
m = 3.8
The difference between both masses are 3.8 - 2 = 1.8 g
Thus, 1.8 g of Helium was added to the cylinder
Answer:
an explanation on how the natural world works
Explanation:
A scientific theory is simply an explanation into how the natural world works. Scientific theory is formulated after a series of hypothesis that has ascertained how true an observation is.
A theory is provides explanation into an observed feature. It can be disproved when new evidences are found. This brings about revision into scientific proofs.
Answer:ugly nlikeieieisj
Explanation:ebebbebebebes