What is Alpha: Definition and 474 Discussions

Alpha (uppercase Α, lowercase α; Ancient Greek: ἄλφα, álpha, modern pronunciation álfa) is the first letter of the Greek alphabet. In the system of Greek numerals, it has a value of one. Alpha is derived from the Phoenician letter aleph , which is the West Semitic word for "ox". Letters that arose from alpha include the Latin letter A and the Cyrillic letter А.

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  1. P

    Exploring the Potential for Habitable Planets in the Alpha Centauri Star System

    I have been reading about the star system on wiki and noticed that one of the Alpha Centauri stars could in theory have a terrestrial planet in the goldilocks region. I also came to know that its orbit would only be stable for 250 million years. Given that these stars have been around for a few...
  2. E

    Electric Potential Difference involving Alpha Decay question

    Homework Statement A plutonium-239 nucleus, initially at rest, undergoes alpha decay to produce a uranium-235 nucleus. The uranium-235 nucleus has a mass of 3.90x10^-25 kg, & moves away from the location of the decay with a speed of 2.62x10^5 m/s. Determine the minum electric potential...
  3. Q

    Force Direction of Alpha Particle in Magnetic Field

    Homework Statement An alpha particle (two protons and two neutrons) traveling east at 2.0 x 105 m/s enters a magnetic field of 0.20 T pointing straight up. What is the force acting on the alpha particle? Homework Equations F = qvBsinøThe Attempt at a Solution With the fingers of the right hand...
  4. R

    Collision between alpha particle and helium atom

    Why their tracks after collision has an angle 90 degree? Any detail derive?
  5. stripes

    Impact parameter of alpha particles

    Homework Statement For alpha particles of 7.7 MeV, what impact parameter will result in a deflection of 2 degrees for a thin gold foil? Homework Equations impact parameter equation, b=\frac{kq_{\alpha}Q}{m_{\alpha}v^{2}}cot\frac{\theta}{2} The Attempt at a Solution Pretty easy, just plug...
  6. S

    Optimizing Alpha Emitters for Efficient Transmutation: A Cost-Effective Approach

    I would like to pursue an idea that involves transmutation of elements using an alpha emitter. I figure that the production rate I would like to achieve would require about 5 Ci of radioactivity. What would be a good candidate, i.e. least expensive and reliable supply with a half life of > 60...
  7. H

    Solving for F_T, F_N, and alpha

    Thank you! A very frustrating problem involving physics, and I finally decided to create an account and ask. And I typed up my problem, equations and all. But as I typed a certain equation, I suddenly wondered why I had cos in one place and sin in another. That was a mistake, and after fixing...
  8. E

    How difficult is it to extract and crystallize alpha-amylase from human saliva?

    I wanted to perform some experiments on enzyme rates and chose amylase as it is easy to obtain. However, I wanted it in pure form so that I can perform mass/concentration-based calculations as well. Is there any way to extract alpha-amylase from human saliva? Thank you.
  9. T

    Alpha Spectroscopy Low Energy Error

    Hello, I've taken a spectrum of a U238 sample, and I keep getting this hill of low energy values. Any ideas as to what could be causing them? Sorry about the weird screenshot; it's the only one I had and my friend couldn't see the dots, so i had to go over them in paint.
  10. N

    Can Teflon Stop Alpha Particles?

    Hi there, I know that alpha particles will pass through gold foil if it is thin enough, but will alpha particles pass through a layer of teflon? If so, is there some way of knowing how thin the teflon should be for most alpha particles to pass through?
  11. J

    Question on calculating mean range of alpha

    Li6(n,a)H3 , Q = 4.78 Mev. The H3 and He4 products are oppositely directed, away from the site of the compound nucleus, and hence they form one straight track. How to calculate the mean range of the alpha particle if the atomic stopping power of helium realtive to air is given as 0.36?
  12. N

    Calculating Alpha: Intercept & K

    Homework Statement calculate alpha using the intercept and the value of k.Homework Equations T= 2pi*(m+(alpha)mspring)/k)^1/2The Attempt at a Solution my intercept i found using EXCEL was .228 and k=5kg/s^2 which I'm pretty sure i did wrong. But i don't know how my intercept would have anything...
  13. S

    Prove alpha=sup(S) is equivalent to alpha belongs to S closure

    Given that alpha is an upper bound of a given set S of real numbers, prove that the following two conditions are equivalent: a) We have alpha=sup(S) b) We have alpha belongs to S closure I'm trying to prove this using two steps. Step one being: assume a is true, then prove b is true...
  14. P

    Curvature radius of alpha and beta particles

    Homework Statement An alpha particle and beta particle, each with kinetic energy 35keV , are sent through a 1.1T magnetic field. The particles move perpendicular to the field. Homework Equations no idea. The Attempt at a Solution theres nothing on curvature radius in my...
  15. L

    Reaching Alpha Centauri in 100 Years: Calculating Speed & Magnitude

    Suppose you wanted to reach Alpha Centauri in 100 years. a. How fast would you have to go, in km/hr3 b. How many times faster is the speed you found in (a) than the speeds ofour fastest current spacecraft (around 50,000 km/hr)?
  16. P

    Alpha, beta particle radius of curviture

    Homework Statement see attachment Homework Equations r=RoA1/3 Ro=1.2*10-15 The Attempt at a Solution 35 kiloelectron volts = 5.60761762 × 10-15 joules I could calculate the velocity if I knew mass but that wouldn't help with the radius? I think that I need to find A from the...
  17. L

    Protein Alpha Helix: Causes and Function

    Homework Statement I'm a little confused as to how exactly a protein folds into an alpha helix...like what causes it exactly to assume that conformation...does it fold spontaneously in water (like i know hydrophobic R groups cause the protein to fold where the hydrophobic groups are faced...
  18. T

    Triple Alpha Reaction: DE's for He4, C12, O16, Ne20

    Hi guys, I posted this in the homework subforum but since its more intensive on the astrophysics side of things I thought I'd give it a shot here. Hope this isn't a problem mods. Helium is burnt via the triple alpha reaction: 3He4 -> C12 at a rate of λ3α(He4)3, where He4 denotes the number...
  19. T

    Astrophysics - triple alpha reaction

    Homework Statement Helium is burnt via the triple alpha reaction: 3He4 -> C12 at a rate of \lambda3α(He4)3, where He4 denotes the number abundance of He4. Write the differential equation for He4 as a function of time. The Attempt at a Solution d(He4)/dt = production - destruction...
  20. K

    What Causes Alpha, Beta, and Gamma Rays?

    What CAUSES alpha, beta and gamma rays?
  21. R

    Question about alpha, the fine structure constant

    I understand that it's been determined to have a very small value. At the same time, it is also true that gravity is incredibly weak compared to the other fundamental forces. What I'm wondering whether there might be some relationship between them?
  22. C

    Radiation HW on Alpha Particles

    Homework Statement How much energy does an alpha particle need to penetrate the minimal protective epidermal layer of skin (Thickness ~7 mg cm-2 Homework Equations Possibly R=0.56E, E,4 OR R=1.24E-2.62, 4<E<8 The Attempt at a Solution I used the equation R=0.56E...
  23. H

    Alpha particle trajectories from Li disintegration

    When a proton is fused with lithium and two alpha particles are formed, how do you know which direction they'll go. I thought they would take roughly the same path as the accelerated proton, but in the explanations of Cockroft and Walton's setup, they show the lithium at a 45 degree angle and...
  24. K

    Alpha Particle speed problem

    Homework Statement An Alpha Particle is emitted with a kinetic energy of 2.34 MeV during a radioactive decay process. The maximum speed of the alpha particle is? Homework Equations KE=mv2 1 ev = 1.6x10-19j The Attempt at a Solution \sqrt{(2.34x10^6)(1.6x10^-19)/4(1.6x10^-27)} Unfortunately...
  25. J

    Reaching Alpha Centauri in human lifetime

    Hello, I'm new on this forum and I hope I will blend in nicely. I happen to have a couple of questions on the Alpha Centauri star in the constellation of Centaurus. I know the distance between this star and our milk way is huge, but suppose one could travel at the speed of light X 25, would...
  26. R

    Alpha Particle Charge: Is it 2x2.50x10^-21?

    Homework Statement What is the charge of an alpha particle? Charge of electron = 2.50x10^-21 Homework Equations The Attempt at a Solution Would you have to multipy 2.50x10^-21 x 2 to get the charge?
  27. J

    Why Does Alpha Emission Occur in Nuclear Physics?

    Hi, quick one: In my nuclear physics notes it says alpha emission is often the only light particle emission that takes place due to its very high binding energy. What I don't understand is that how come the nucleus wants to retain binding energy? I would have thought that it wants to get...
  28. L

    System of linear equations with alpha variable

    Homework Statement For which value of alpha does the following system of linear equations have a solution? x + y = 2 x +αy = -1 αx + y = 1 The Attempt at a Solution I put it into a matrix that looks like this: 1 1 | 2 1 α | -1 α 1 | 1 Then I subtracted row1 from...
  29. M

    Creating a Quadratic Equation with Inverted Roots

    Homework Statement The quadratic equation x^2 + kx + 2k = 0 where k is a non-zero constant, has roots \alpha and \beta. Find a quadratic equation with roots \frac{\alpha}{\beta} and \frac{\beta}{\alpha}. {one is meant to be inverted - the code isn't working properly :( } Homework...
  30. F

    What is the equation for sine alpha when alpha is greater than 90 degrees?

    [PLAIN]http://img266.imageshack.us/img266/8206/triangles.png This is not a homework question, but it is something I can't wrap my mind around. What is the equation for sine alpha where alpha is greater than 90 degrees? For the first triangle its easy: sine alpha = b/c But what is it for...
  31. H

    Why Alpha Particle Decay Q Leads to Lifetime Change

    Hi, I want to know why a small change in energy released, Q, in alpha particle decay leads to a large change in the lifetime. Also could anyone provide me with a link that shows a diagram of the energy spectrum of alpha particles. Thanks.
  32. K

    Formation of 17O Nucleus from 14N + Alpha Particle

    Homework Statement An alpha particle is bombarded on 14 N. As a result a 17 O nucleus is formed, and a particle is emitted. This particle is a: (a) neutron (b) proton...
  33. S

    Kinetic energy of alpha particle during decay

    Homework Statement Show that kinetic energy acquired by an alpha particle during an alpha decay is Talpha=Q/[1+[maplha/mD] Homework Equations Q=[mP-mD-malpha]c^2 The Attempt at a Solution Q is the release of energy which is acquired by the daughter nucleus and the alpha...
  34. S

    Alpha decay and its relationship to speed

    I need some explanation to what I must know in order to solve the next problem. A step by step process and mention of the particular concept I must know would be greatly appreciated as I must learn how to do this by june 8. " In the alpha decay of a Uranium-238 nucleus, what is the ratio v/V...
  35. Orion1

    Wolfram Alpha: Your Ultimate Online Computational Knowledge Engine

    https://www.youtube.com/watch?v=<object width="640" height="385"><param name="movie" value="http://www.youtube.com/v/60P7717-XOQ&hl=en_US&fs=1&"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed...
  36. L

    Alpha Decay of Polonium-210 Homework

    Homework Statement Polonium isotope {}_{84}^{210}Po is unstable and emits a 5.30MeV \alpha particle. i. Indentify the daughter nuclide (using a periodic table) ii. Calculate the mass of the daughter nuclide. Homework Equations Mass of neutral {}^{210}Po nuclide is 209.9829u Mass of...
  37. I

    Question about alpha particles

    Radium decays emitting alpha particles into Radon. i) Explain, in terms of momentum of the particles, why the radon nucleus and the alpha particles move off in opposite directions after the reaction. ii) The speed of the radon nucleus after the reaction is v_{R} and that of the alpha...
  38. L

    Why Is Helium Safe to Inhale but Alpha Particles Are Harmful?

    Why is it safe to suck the helium out of a balloon, but it is dangerous to ingest alpha particles? I guess the main question is what is the difference between an alpha particle and a helium atom? Aren't they both written as \stackrel{4}{2}He?
  39. L

    Distance of alpha particle to gold nucleus

    1. The predictions of Rutherford's scattering formula failed to correspond with experimental data when the energy of the incoming alpha particles exceeded 32MeV. This can be explained by the fact that the predictions of the formula apply when the only force involved is the electromagnetic force...
  40. A

    Could We Send a Probe to Alpha Centauri with Current Technology?

    I Have read a lot recently about Alpha centuri having a planet that's identical to earth. i qquote On January 15, 2010, a team of astronomers released the results of computer simulations indicating that kilometer-size planetesimals can form and accrete into rocky Earth-size planets around...
  41. W

    Binding energy of the alpha particle

    Homework Statement Calculate the difference between the binding energy of a nucleus of carbon 12 and the sum of the binding energies of three alpha particles. Assuming the carbon 12 is composed of three alpha particles in a triangular structure, with three effective "alpha bonds" joining them...
  42. S

    Calculating Alpha Neutron Reaction Energy for Beryllium

    Homework Statement Calculate the energy released in the alpha neutron reaction for beryllium. The mass of beryllium is 9.012183u. ^{4}_{2}He + ^{9}_{4}Be \rightarrow ^{1}_{0}n + ^{12}_{6}C Homework Equations The Attempt at a Solution Tried finding the total binding energy for both...
  43. F

    How Do You Calculate the Momentum of an Alpha Particle?

    Homework Statement An alpha particle (a helium nucleus, containing 2 protons and 2 neutrons) starts out with kinetic energy of 10 MeV (10*10^6 eV), and heads in the +x direction straight toward a gold nucleus (containing 79 protons and 118 neutrons). The particles are initially far apart, and...
  44. M

    Rutherford's experiment alpha source

    Rutherford investigated the scattering of alpha particles by gold foil in an evacuated container. The evidence from his investigations led to the nuclear model of the atom. Why was it important for this investigation that the alpha source was inside the container?
  45. M

    N-14 + alpha -> O-17 + proton

    N-14 + alpha --> O-17 + proton N-14 + alpha particle --> O-17 + high energy proton alpha particle used was 7.70MeV. Q1. Calculate the energy to be shared in the interaction. Q2. Explain why the proton cannot take all of the available energy. The following date is given for...
  46. C

    Minimum Electrical Potential Difference required to stop Alpha particle

    Homework Statement A plutonium-239 nucleus, initially at rest, undergoes alpha decay to produce a uranium-235 nucleus. The uranium-235 nucleus has a mass of 3.90 x 10-25 kg, and moves away from the location of the decay with a speed of 2.62 x 105 m/s. Determine the minimum electric potential...
  47. K

    Why Does Alpha & Beta Particle Emission Occur in Radioactive Nuclei?

    Do we know why radioactive nuclei only decay through emission of alpha and beta particles? There is spontaneous fission in some cases, of course, but what I mean to ask is, why should just a proton or just a neutron or a particle X with 2 protons and 3 neutrons, or whatever else not be emitted...
  48. J

    How can I build a large alpha particle generator for He++ production?

    I am looking to source (build) a large alpha particle generator that creates (mostly) He++ and not He+ particles. Thanks.
  49. N

    Alpha, Beta, Gamma , neutron ray, which one is harmful?

    Homework Statement If you were given 4 cookies, each emitter different ray 1)Alpha, 2)Beta,3) Gamma , 4)neutron You have to make decision of the following: a)eat one of the cookies b)dispose one of the cookies at storage facility called WHIP c)put one of the cookies in your pocket...
  50. S

    How can Uncertainty principle be used to get speed of alpha particle

    assuming that Delta p = aprroxiamtely p, how can the uncertainty principle, be manipulated in order to achieve the speed of an alpha particle trapped in a nucleus of just say uranium 238 with proton number 92 ? or any other nucleus...what is the main manipulation steps of the formula?would...
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