Imagin that point source is positioned at the origin of a sphere. Assume a monoenergetic isotropic photon source, emitting 10^9 photons s^-1, each with a frequency of 2.7 x0 10^20 Hz.
a.)Calculate the energy fluence rate [MeV cm^-2 s^-1] at a radial distance of 20 cm from the source...
An x-ray field at a point P contains 7.5 x 10^8 photons/m^2-sec-keV, uniformly distributed from 10 to 100 keV.
a.) What is the photon flux density at P?
b.) What would be the photon fluence in one hour?
c.) What is the corresponding energy fluence in SI units?
work shown:
a.) 7.5...
energy flux density and and energy fluence question! work shown please help!
A point source of Co-60 gamma rays emits equal numbers of photons of 1.17 and 1.33 MeV, giving a flux density of 5.7 x 10^9 photons/cm^2-sec at a specified location.
a.)What is the energy flux density there...
An x-ray field at a point P contains 7.5 x 10^8 photons /m^2-sec-keV uniformly distributed from 10 to 100 keV.
a.) What is the photon flux density at P?
b.) What would the photon fluence in one hour?
c.) What is the corresponding energy fluence in SI units?
my work:
a.) 7.5 x 10^8...
Imagine that a point source is poisitioned at the origin of a sphere. Assume a monoenergetic isotropic photon source, emitting 10^9 photons*s^-1, each with a frequency of 2.7 x 10^20 Hz.
a.) Calculate the energy fluence rate [MeV cm^-2 s^-1] at a radial distance of 20 cm from the source...
Model the arterial tree as a simple branching network in which each junction is composed of a parent vessel and daughter vessels, each having a diameter related to the parent's via the cube law (D_n-1)^3= (D_n*a)^3 + (D_n*b)^3 which is approx. equal to 2*(D_n)^3
a.) Show that D_n/D_0=...
Consider the following H1 NMR signal from the human brain obtained at 1.5 T
S(t)= S(0) { 3 exp (-iw_NAA*t)* exp (-t/T2_NAA*) + exp(-iw_Cr*t)*exp(-t/T2_Cr*) +
exp(-iw_Cho*t)*exp(-t/T2_Cho*)}
where the 3 terms shown rep. the contributions from the major peaks of total...
since t>0 and |t|=t and for t< 0 |t|= -t
and since the inverse Fourier transform integral for t>=0 is given .. .u can add the the results for the inverse transform for t<=0 to the result to get Ge(f)
however, how do u integrate the expression for
neg. infinity to zero for integral of...
in that case.. is the solution for X and part b correct?
if that's the integral... it is an imaginary integral so how do u solve that part.. I'm confused?
Suppose that you obtain a one dimension magnetic resonance image from two water-filled cubic shaped containers arranged as shown below. This diagram is a cross-section of the cubic containers in the x-y plane.
figure description:
-one of cube's is 2 cm wide, the other is 1 cm wide, and...
i forgot to include the echo signal info Se(t) info, which can be rep. by
Se(t)= Se(0) exp (i(2pi(f0)(t))* exp (-|t|/T2*) from negative inf. to inf
therefore, since the |t| is the magn. of t,
therefore i assumed the img. part can be ignored which was helpful in my assumption. in my...
The "Free Induction Decay signal" (FID) is a particular type of NMR signal observed in both MRI and MRS. An idealized representation of the signal Sf(t) is given by
Sf(t)= Sf(0) exp (-i2pi(f_0)(t))*exp(-t/T2*) t>=0
Sf(t)= 0
it was proven that Gf(f) corresponding to this signal is given...