Ernest Rutherford, 1st Baron Rutherford of Nelson, (30 August 1871 – 19 October 1937) was a New Zealand-born British physicist who came to be known as the father of nuclear physics. Encyclopædia Britannica considers him to be the greatest experimentalist since Michael Faraday (1791–1867). He also spent a substantial amount of his career abroad, in both Canada and the United Kingdom.
In early work, Rutherford discovered the concept of radioactive half-life, the radioactive element radon, and differentiated and named alpha and beta radiation. This work was performed at McGill University in Montreal, Quebec, Canada. It is the basis for the Nobel Prize in Chemistry he was awarded in 1908 "for his investigations into the disintegration of the elements, and the chemistry of radioactive substances", for which he was the first Oceanian Nobel laureate, and the first to perform the awarded work in Canada.
Rutherford moved in 1907 to the Victoria University of Manchester (today University of Manchester) in the UK, where he and Thomas Royds proved that alpha radiation is helium nuclei. Rutherford performed his most famous work after he became a Nobel laureate. In 1911, although he could not prove that it was positive or negative, he theorized that atoms have their charge concentrated in a very small nucleus, and thereby pioneered the Rutherford model of the atom, through his discovery and interpretation of Rutherford scattering by the gold foil experiment of Hans Geiger and Ernest Marsden. He performed the first artificially induced nuclear reaction in 1917 in experiments where nitrogen nuclei were bombarded with alpha particles. As a result, he discovered the emission of a subatomic particle which, in 1919, he called the "hydrogen atom" but, in 1920, he more accurately named the proton.Rutherford became Director of the Cavendish Laboratory at the University of Cambridge in 1919. Under his leadership the neutron was discovered by James Chadwick in 1932 and in the same year the first experiment to split the nucleus in a fully controlled manner was performed by students working under his direction, John Cockcroft and Ernest Walton. After his death in 1937, he was buried in Westminster Abbey near Sir Isaac Newton. The chemical element rutherfordium (element 104) was named after him in 1997.
Hello everyone,
I am working on this problem and I think I almost solved it, but then I noticed, that I do not know what values I have for dn, n and dθ.
Can anyone help me with this?
With regard to Rutherford's atomic model, and Rydberg's discovery in general for the hydrogen distribution lines, what does Rydberg's constant physically mean? Its unit is m ^ -1, as if it were a rate, but it was not clear to me its physical meaning.
And why does it grow with atomic mass...
Hi,
New to the forum here! I'm teaching age 16-18 physics in the UK. I was wondering if anyone in here might have experience using equipment that looks like this:
https://www.eiscolabs.com/products/alpha-scattering
It's a physical analogue of Rutherford's famous experiment: roll ball bearings...
I have the equation but I am unsure of what my r min would be. Is it the sum of the radii or the difference? I am also confused on what z1 would be. I am fairly sure z2 is the atomic number of Fe(26) but I am unsure of this as well.
Edit: I just read that z1 could be 2, is this correct?
The experimental observation of finding very few alpha particles scattered through large angles (>90) - I thought this would have inferred that the positive charge of the core of the atom (which we now come to know as the nuclei) must have been great in order greatly deflect alpha particles...
Hello, I am reading a section in Jackson discussing classical Rutherford scattering, and he mentions incorporating a cutoff in the Coulomb interaction in order to model electric screening. I am trying to understand how he applies this, as described below.
The set up is basically the classic...
Homework Statement
Question
a) Briefly describe the Rutherford model of the hydrogen atom and mention any inadequacies that it might have.
b) Describe the Bohr model of the hydrogen atom, and indicate the significance of the quantum number 'n' in the Bohr model.
Homework EquationsThe Attempt...
Good afternoon. Which modifications did the Bohr model introduce into the Rutherford one to justify the Discountinuous atomic spectra, specially the one for the Hydrogen atom?
Thanks
Homework Statement So I recently carried out an experiment for Rutherford scattering. From my lab script is states the following
'Recording the scattering rate as function of angle
In order to compare your results with “Rutherford’s scattering formula”, you must first make a
correction for the...
Homework Statement
What errors did Rutherford encounter in his experiment and how did he account for them.
Homework Equations
I believe there is an equation to find (b) but I don't know what it is.
I read from a text that Rutherford found out that all the mass must be concentrated in the middle of the atom due to fast-moving alpa ( high momentum) is deflected back at 180 degrees.
I am wondering if there is going to be no contact collision due to the the kinetic energy being converted...
I'm a Physics undergraduate at University and in my labs module I had to recreate the Rutherford Scattering experiment. The basic setup was similar to this:
My problem is that this setup only records data in one plane and not 3D. In reality the particles are scattered in a sort of cone...
Homework Statement
Show that the largest possible change in the kinetic energy , ##\Delta E_{kin}##, of a particle of mass ##m## running into another particle of mass ##M## at rest in the lab coordinate system is
\Delta E_{kin} = \frac{-4AE_{kin}}{(1+A)^{2}}, where ##A = \frac{M}{m}##...
Hi I am revising for an exam and am a bit confused with Rutherford Scattering
- Finding the cross section (is the cross section different to the differential cross section?)
- Finding the solid angle.
So here is a past question: A beam of 6MeV alpha particles is incident on a platinum foil. A...
Homework Statement
Onto an Aluminium 50μm thick plate, we send a beam of alpha particles with unknown kinetic energy. the cross section of the beam is 2cm2, density 1013 / scm2 . Whats the kinetic energy of the particles if every second we sense 105 scattered particles between the angles 40°...
Homework Statement
The difference between Rutherford's and Bohr's theory of atom is ...
A. Bohr's spectrum of hydrogen atom is discrete while Rutherford's continuous
B. Bohr's stated electron goes around the nucleon while radiating energy, while Rutherford's not radiating energy.
C. Bohr's...
Homework Statement
I am given a numerical example (to be solved with pen, paper and calculator only) of an RBS spectrum of a AuAgCu-alloy on a glass-substrate. The question is "Can you get the composition? How accurate is the result?Homework Equations
All the Rutherford Backscattering...
How do we know that the nucleus is at the center of the atom?
I know about the Geiger/Marsden experiment and also of its results. They observed a few α-particles scattering almost at 180°. Hence they concluded that there must exist a high density, positively charged "center" in the atom. But on...
Homework Statement
I am trying to show that as the alpha particle is being scattered, the angular momentum magnitude at point M is m r^2 \frac{d \phi}{dt}.
Diagram:
Homework Equations
Linear Momentum: ##\vec L = \vec r \times \vec p ##
Repulsive Coulomb Force: ##\vec F = \frac{k 2Ze^2}{r^2}...
Homework Statement
Calculate the cross section for the scattering of a 10 MeV alpha particle by a gold nucleus (Z=79, A=197) through an angle greater than a) 10 degrees b) 20 degrees c) 30 degrees. Neglect Nuclear recoil.
Homework Equations...
Homework Statement
Carbon scatters on a proton. What is the limit of the angle of scattering?
I'm not really sure where to start this question. I know it has something to do with Rutherford Scattering and impact parameter.
Homework EquationsThe Attempt at a Solution
I'm doing high school physics and if a question says something like: A radioactive source gives count rate of 110 counts per second
Can you say that the ACTIVITY is also 110 bq? My second question is how would a gieger counter detect gamma radiation? It is the least ionising of all three...
Homework Statement
Hi there. This is not really a problem, I am only trying to understand something but I simply can't.
So Rutherford scattering says that $$ \frac{d\sigma }{d\Omega}=(\frac{Ze^2m}{8\pi \varepsilon _0 p^2})^2\frac{1}{\sin ^4(\Theta/2)}|F(q)|^2$$ where $$F(q)=\int \rho (\vec...
Hi,
I was just wondering if someone could help clarify how pi - theta = phi?
That is the link to the youtube video I was watching, the guys pretty good check him out if you want to learn how to derive the differential scattering cross section.
Homework Statement
[/B]
b) For a Form factor of form ##\theta_{(1-r)}## and ##\frac{1}{1 + e^{\frac{r-R}{a}}}##, how will these change when ##r \rightarrow 2r##?
c) How would one accelerate and observe scattered protons?
Homework EquationsThe Attempt at a Solution
Part(b)
[/B]
Rate of...
Homework Statement
In 1911, Ernest Rutherford discovered the nucleus of the atom by observing the scattering of helium nuclei from gold nuclei. If a helium nucleus with a mass of 6.68 10^-27 kg, a charge of +2e, and an initial velocity of 1.30 10^7 m/s is projected head-on toward a gold...
Homework Statement
derive an equation for the solid angle for a Rutherford scattering detector given a detcor window area of A and a distance to the detector of D for some scattering angle \phi given that d\Omega =2\pi sin\phi d\phi
Homework Equations
d\Omega =2\pi sin\phi d\phi
A=Dd\phi
The...
Homework Statement
In the famous “Rutherford backscattering” experiment, alpha particles (Z=2) of
approximately 7 MeV were used to bombard a Au (Z=79) film. Rutherford derived the
scattering formula by treating an incident alpha particle and a Au target atom as two point
charges with...
Hi everyone. I have a question about the calculation of Rutherford cross section in the context of QED. I know how to compute it using the usual four potential:
$$
A_\mu(q)=(\frac{e}{q^2},0,0,0)
$$
and taking the matrix element to be:
$$
\mathcal{M}=\bar u_{s'}(p')\gamma_\mu...
I'm writing a program for simulating the angle distribution of scattered particles from a gold nucleus but I doubt the results. I don't know...But it would be very good if someone check it and give some hints.
I also want to ask should I vary both initial speed and impact parameter in one...
Hi,
My question is about the famous paper by E. Rutherford on the scattering of alpha particles (1911). The paper is easy to find on internet. Rutherford gives the formula for the electric field inside an atom, at a distance r from the nucleus (here reduced to a point):
X = N e (1/r^2 - r/R^3)...
I know there are other things that fail about the rutherford atom
but as the electron is accelerating and radiating away energy it would fall into the nucleus, my question is how much energy would the electron need to gain so that the classical atom could be stable
a hydrogen atom for example
Hi,
Homework Statement
I performed the Rutherford experiment the other day, using Au thin foil of 2μm, a source/gun of α particles (241Am) and a detector/counter. α particles were shot from the source through a slit of 20mmX1mm (presumably attached to the foil, thus narrowing the effective...
Hello, I have just started reading my first chemistry book and have a question about Rutherford's experiment.
As stated in the book:
Thomson's model of the atom suggests that positive and negative charges were evenly distributed around the atom. Then Rutherford came with his experiment: he...
Homework Statement
I'm trying to work out the derivation of the the Rutherford scattering trajectory. I understand the conservation of linear momentum, and that the only force acting is the coulomb force between the incoming particle and the target nucleus. Early on in the derivation I'm...
Homework Statement
The fraction of 6.0 MeV protons scattered by a thin gold foil, of density 19.3 g/cm^3, from the incident beam into a region where scattering angles exceed 60° is equal to 2.0(10^-5). Calculate the thickness of the gold foil.
Homework Equations...
Homework Statement
We want to fin an expression for \theta, the Rutherford scattering angle.
I have an expression that I derived for a hyperbolic trajectory, of the form \frac{(x+x_0)^2}{A^2}-\frac{y^2}{B^2} = 1. We wanted it in terms of α, ε, where α is a constant ( \alpha =...
Homework Statement
Asked to calculate the relativistic correction, to the differential scattering cross section which is given by the equation below in terms of E, E0 and θ where E0= .511 MeV.
with 100MeV electrons from an Au nuclei at certain angles θ.
Homework Equations
Relativistic...
Homework Statement
Homework Equations
If i can make that out its Ep=kq1q2/r where k is coloumbs constant
The Attempt at a Solution
Im a little confused how do i know the radius of the alpha particles?
I was thinking its conservation of energy, Ep+Ek=Eka then try to solve for...
Hi
I need to plot the (differential) Rutherford cross section as a function of the scattering angle in the CM frame. the reaction is a typical projectile on stationary target. I know the projectile energy in the lab, θcm and the masses. I am confused over which energy to use though.
I know...
Hello everyone
I have been supplied with this eqn
n=\frac{Nat}{16r^2}(\frac{2Ze^2}{4\pi\epsilon_0E_K})^2cosec^4(\frac{\phi}{2})
for Rutherford scattering.
N is the number of alpha particles incident on a unit area of foil
t is the thickness of the foil
a is the number of atoms...
Homework Statement
Given variables and data: flux of alpha particles;Z; T-kinetic energy of the flux;
t-thickness of the target.I have to calculate the number of alpha particles which are
scattered in angle θ>60 degrees.
Homework Equations
1) Is my formula correct ( see below) if I am...
Homework Statement
I'm taking a graduate level course in classical mechanics that uses Goldstein's book. We are currently discussing scattering in a central field in chapter 3. Here are two problems that might be very basic/standard scattering problems, yet I'm not how to proceed or get...
Hi,everyone!I have a problem!As known to us all,in Rutherford scattering experiment α rays are used to bomb gold foil, and most of them pass through the gold foil.But today I read something about the characteristics of α particles,the book says that you can stop α rays with a piece of paper...
Homework Statement
Hey I am revising for my physics test and am having a bit of trouble understanding rutherford's alpha scattering experiment. My teacher gave us a powerpoint but it does not seem to help me, more so it confuses me. I am a good physics student and not understanding this is...
differential cross section of coulomb scattering can be expressed as a form factor times Rutherford one, we model the charge we used spherically symmetric charge density, if we replace this point charge with other distribution like Gaussian , what is the difference between these two models, is...
here is an excerpt i found on the web.
Ernest Rutherford, born on New Zealand, showed in 1911 that alpha particles were sometimes very strongly scattered by the positive charges of the atom, in a way that could only be explained if such charges were concentrated in a very small volume...
Rutherford scattering experiment question (urgent)
Homework Statement
I need to find the value of the electrical force between the alpha particle and the nucleus of the atom at the point of closest approach.
Closest approach = 7.27 x 10^-14 m
Charge on atom = (79 * 1.60 x 10 ^-19) C
initial...