Proton Definition and 835 Threads

Homework Statement Charged particles such as protons are accelerated to high velocities and are allowed to collide with atomic nuclei to probe their internal structure. The electric potential outside of a point charge Ze. A) A lead nucleus (Z - 82) is approximately described as a sphere of...

Homework Statement Two photons collide and create an electron-positron pair: y1+y2 -> e-+e+ If the wavelength of y1 is 1 mm calculate the energy threshold for photon y1 to produce the electron-positron pair. Suppose E(y1)=hc/\lambda2 where \lambda2 =1.1 mm Hints: In the center of...

Homework Statement http://imageshack.us/photo/my-images/543/15jd.jpg/ [IMG=[PLAIN]http://img543.imageshack.us/img543/8674/15jd.jpg][/PLAIN] Homework Equations Qnet outside sphere = Q1+Q2 KEi + PEi = KEf + PEf q = 1.6E-19 mass of q = 1.672E-27 The Attempt at a Solution +(q ∫ KQ1 / R^2 ]...

Most of the proton REST mass is energy anyway. So how does that work?

Homework Statement An electron and a proton are separately placed at rest midway between two oppositely charged metal plates. A) Which way will the electron accelerate? B) Which way will the proton accelerate? C) Which particle, if either, will acquire more kinetic energy just before striking...

Could anyone guide me through this problem? https://www.physicsforums.com/showthread.php?t=348863 Just need to get started. Note that this would need to be solved in the proton rest frame.

A high energy proton can collide with a photon to produce a charged pion and a neutron. If the photon comes from the cosmic microwave background and has an energy equivalent to a temperature of 3 K, what is the minimum energy of the proton in eV necessary to allow this reaction? I'm thinking...

Homework Statement Some of the earliest atomic models held that the orbital velocity of an electron in an atom could be correlated with the radius of the atom. If the radius of the hydrogen atom is 10^−10 m and the electrostatic force is responsible for the circular motion of the electron...

I asked this question because I think that acceleration could be positive (though I may be wrong.) Homework Statement The electric field near the Earth's surface has magnitude of about 150 \text{N/C} . What is the acceleration of the proton? Homework Equations Clearly, we need to use...

Proton Decay- What happens to the proton after "too many decays"? Let me start off by saying that I am not the brightest individual, but I am curious about things from time to time (hence my name and hence why I'm here). So please excuse my stupidity if it shows too much. Anyway, recently, I...

Homework Statement A Proton moves with a velocity of 5x10^6 m/s in the +y direction. What is the force (magnitude and direction) on the proton if a magnetic field of 2.12Ti + 2.12Tj is applied. Homework Equations - F = |q|vBsinθ - Right hand rule to find direction The Attempt at a...

http://www.russianspaceweb.com/proton_glonass49.html#culprit Seems like a simple mechanical interlock (notch or flat) could have prevented this problem. http://xkcd.com/1133/

Homework Statement If an electron and proton (both initially at rest and far apart) come together to form a hydrogen atom, 13.6 eV of energy is released (mostly as light). By how much does the mass of an H atom differ from the sum of the electron and proton masses? What is the...

1. A moving proton has 6.4 x 10-16 J of kinetic energy. The proton is accelerated by a potential difference of 5 000 V between parallel plates. The proton emerges from the parallel plates with what speed? a) 1.3 x 106 m/s b) 8.8 x 105 m/s c)1.8 x 106 m/s d) 9.8 x 105 m/sHomework Equations...

Homework Statement Estimate the minimum proton lifetime from the fact that you haven't yet died from internal radiation. Use the following conditions: 1.) At a dosis of Dmax = 2 Greys per year (Jkg-1 yr-1) you would already be dead. 2.) The human body is made mostly of water. 3.) The total...

Homework Statement a proton moves with a velocity <6*105,3*105> m/s through a magnetic field given by <.2,.2> T a. Find the magnetic force per unit charge on the proton b. Find the work done by this forceHomework Equations Fm=qv x BThe Attempt at a Solution For part a, I used a property of...

Hello, I regard a particle in an accelerator. The particle has the kinetic energy of 7TeV. I have callculated the momentum $$ E=pc+mc^2\\ \Rightarrow p=\frac{1}{c} \sqrt{E^2 -(mc^2)^2} =7,00094~ TeV/c $$ After that I want to callculate the "velocity" and the " \gamma-factor". But I...

1. a) A relativistic proton has a momentum of 10x10^-18 kg*m/s. The rest energy of a proton is 0.150nJ. The kinetic energy of the protoon b) In this situation the speed of the proton is? 2. E=MC^2 P= MV/sqroot(1-(v^2/c^2) K=[MC^2/ sqroot(1-v^2/c^2)]-[mc^2] 3. The algebra in this problem...

Hello all, I know that MRI is focuse on Hydrogen proton, but I don't understand if it focuse just in the Hydrogen proton that in water (Liquids) of the body or in all the Hydrogen proton that are within the molecules in the body. In relation to this, how the MRI could distinguish...

So I recently heard of a simple way of thinking about how the emission of an alpha particle is "beneficial" to a nucleus being stable. The argument goes as follows: "Let's say we have a nucleus that is unstable because the electric repulsion of protons can't balance out the strong force...

Homework Statement The electric field at a location C points north, and the magnitude is 1*10^6 N/C. Where should you place a proton and an electron, at equal distances from C, to produce this field? Give a numerical answer and a direction for each particle (North, South, East or West)...

Simple question, please help. I think it belongs in this forum, though I apologize if there's a nuclear physics forum or somewhere else I should put this. I came across this thread when trying to figure out why electrons don't rest at zero distance away from the nucleus of an atom. So as I...

Homework Statement What is the electric potential energy of a proton located 20.0 A (one angstrom or 1A is equal to 10^-10m) from another proton? Homework Equations Ep= F x d F= kq1q2/r^2 The Attempt at a Solution Ep= Fxd F=kq1q2/r^2 therefore Ep = (Kq1q2)(d)/r^2 d=r so...

Homework Statement A natural lithium target 3.8 mg cm-2 thick is bombarded with a 125 µA beam of 3.5 MeV protons initiating a 7Li(p,n) reaction. Assuming a reaction cross section of 300 mb, calculate the activity produced by a 15 minute bombardment. Homework Equations...

Homework Statement The elastic form factors of the proton are well described by the form G(q2) = \frac{G(0)}{(1 + (\frac{q^{2}}{0.71})^{2}} with qw in GeV2. Show that an exponential distribution in the proton given by ρ(r) = ρoe-λr Homework Equations thought it to be the...

Homework Statement So I just wrote my midterm in physics, and I was curious on how to do the last question. Parallel plates, length 5.5cm, Distance between them is 0.3 cm Electric Field (E) is 5.4x10^4 Asking what is the initial speed of a proton going through the parallel plates if it just...

Homework Statement a proton is confined in an infinitely high square well of length 10 fm. If the proton transitions from n=2 to ground state determine the energy and wavelength of the photon emitted Homework Equations E = \frac{h^2 n^2}{8mL^2} E = \frac{hc}{\lambda} \ \ or \ \...

Homework Statement (see attachment) Given data: 1.The speed of light in empty space is ##3 \times 10^8 m/s##. 2.The mass of the proton is ##1.67 \times 10^{-27} kg## . 3.The speed of light in water is ##2.3 \times 10^8 m/s##. 4.When photon emission begins to occur the initial proton, the final...

An electron is initially 2cm from a proton and is then give an initial velocity away from the proton. If v is 31m/s how far to the right does the electron move before it momentarily stops? is this right? http://i1341.photobucket.com/albums/o745/nebula-314/IMAG0112_zps5361921d.jpg

Homework Statement (a) Calculate the speed of a proton that is accelerated from rest through an electric potential difference of 121 V. (b) Calculate the speed of an electron that is accelerated through the same potential difference.Homework Equations The Attempt at a Solution I actually...

I'm asked to state whether or not a proton and an antiproton can annihilate into an electron, a positron, and an electron neutrino. p + \overline{p} \rightarrow e + e^+ + \nu_e It doesn't seem allowed to me but I can't fully justify it with any conservation law. I've reasoned that...

Homework Statement A charged particle (either an electron or a proton) is moving rightward between two parallel charged plates separated by distance d = 1.90 mm. The particle is slowing from an initial speed of 93.5 km/s at the left plate. The left plate has V=-70V and the right plate has...

Homework Statement It asks you to identify the shift and nature of the protons in the molecule. Picture: https://mailhost-6.tamu.edu/service/home/~/?auth=co&id=24393&part=2 Homework Equations none The Attempt at a Solution I cannot understand what makes C a multiplet...

Homework Statement Proton is moving in the homogen magentic field with B=0,1T. Mass of proton is 938MeV/c02. How much is the radius of helix at which proton is moving, if his speed is 0,99*c0, and the angle between helix and magnetic field is 60°. Homework Equations...

Homework Statement A proton moves in a spiral path when enters a magnetic field of 5 T. If the pitch is 5 cm, find the angle between v and B. Homework Equations F = B q v sin θ F = m v2 / r The Attempt at a Solution I am guessing that I need to break down the velocity into two...

If a proton, a neutron and an electron have the same total energy than rank the the particles in terms of most momentum to least momentum This is the first problem I attempted after learning about special relativity. I used the equation E^2 = \rho^2 c^2 + (m c^2 )^2 Since the energy is...

Some researchers seem to have measured the proton as being 4% smaller than previously thought: http://www.nature.com/news/shrunken-proton-baffles-scientists-1.12289 What is the reason for this? This is the second time the experiment has been conducted. If it is carried out yet again...

sciencemag.org/content/339/6118/417 How far-reaching are the implications of this? Presumably it could add support to or help disprove certain theories that predict the larger radius as compared to what was found. It's mind boggling, really. I'd have to say this is on par with the discovery...

A usual lore from chiral perturbation theory is that the mass of the pion is proportional to the sum of the up and down masses, and then it is going to be zero when such masses are zero. Now, for the proton, I notice the following remark from Chris Quigg Why is it different of the pion?

Homework Statement A positive charge is moving straight ahead in a magnetic field going out of page. What is the direction of force on the positively charged particle? The Attempt at a Solution I know that you use the right hand rule where fingers show direction of force. But I'm...

Homework Statement a) Calculate the kinetic energy required to accelerate a single proton from a rest position to 0.9999c. The mass of a proton is 1.67*10^-27 Kg. b) Find the ratio of kinetic energy to the energy of a proton at rest Homework Equations Ekrest = mc2 Ek=...

Part 1----------------------------------------- Ok, the site I have just read through is http://burro.astr.cwru.edu/stu/stars_lifedeath.html one. I have a few questions about it. Firstly, about the fusion of helium into hydrogen... http://burro.astr.cwru.edu/stu/media/fusion.jpg It...

Or, more generally, can we destroy a nucleon? I know we can convert between a proton and a neutron, but what about obliteration? If we try to separate a quark from a nucleon we cannot do so because we bud off an anti-quark and the original quark goes back in (or something like that). So we...

Would it just be the same as with two electrons? (or any other pair of particles with the same charge) I'm kinda in two minds, I suspect that is wrong because wouldn't the fact that they attract each other (instead of repelling) means that the diagram would be drawn differently?

The following problem appeared on the A2 Edexcel Physics unit 4 exam paper January 2012 question 18. The solution, as given by the exam board, is attached. Question: 18. James Chadwick is credited with discovering the neutron in 1932. Beryllium was bombarded with alpha particles, knocking...

Homework Statement A mass spectrometer uses either a magnetic field or an electric field to deflect charged particles. A proton starts from rest a plate P. The Speed of the proton as it passes through the hole in plate Q is? V= 10000 V Mass of a proton = 1.67x10^-27 Charge of a proton...

It had been asked before on physics forums but the given answers didn't convince me .

The mass of proton is 938mev/c2 where as mass of quarks in proton is 11 Mev/c2. Much of the reminder is gluon. But gluon does not have any mass. So how can it be gluon? Also in neutron decay, one d Quark transform itself into u quark by absorbing / emitting W boson. in this case W boson is...

Proton electric dipole moment... what's that all about?

Homework Statement Here is the problem given. The answer is E. Homework Equations No equations are given. Assumed use of standard equations for electric field and force involving electric field. The Attempt at a Solution I tried using a few equations (E = F/q0), (F = mv^2)...