mass spectrometer

Examples of mass spectrometer in the following topics:

• Mass Spectrometer

  • Mass spectrometers use electric or magnetic fields to identify different materials.
  • Mass spectrometry (MS) is the art of displaying the spectra (singular spectrum) of the masses of a sample of material.
  • Mass spectrometers, as diagramed in , separate compounds based on a property known as the mass-to-charge ratio.
  • The elements or molecules are uniquely identified by correlating known masses by the identified masses.
  • Schematics of a simple mass spectrometer with sector type mass analyzer.

• Examples and Applications

  • Cyclotrons, magnetrons, and mass spectrometers represent practical technological applications of electromagnetic fields.
  • We will explore some of these, including the cyclotron and synchrotron, cavity magnetron, and mass spectrometer.
  • The following figure illustrates one type of mass spectrometer.
  • The mass spectrometer will segregate the particles spatially allowing a detector to measure the mass-to-charge ratio of each particle.
  • Schematics of a simple mass spectrometer with sector type mass analyzer.

• Circular Motion

  • The curved paths of charged particles in magnetic fields are the basis of a number of phenomena and can even be used analytically, such as in a mass spectrometer. shows the path traced by particles in a bubble chamber.
  • Here, r, called the gyroradius or cyclotron radius, is the radius of curvature of the path of a charged particle with mass m and charge q, moving at a speed v perpendicular to a magnetic field of strength B.
  • The radius of the path can be used to find the mass, charge, and energy of the particle.

• The Spectrometer

  • A spectrometer uses properties of light to identify atoms by measuring wavelength and frequency, which are functions of radiated energy.
  • A spectrometer is an instrument used to intensely measure light over a specific portion of the electromagnetic spectrum, to identify materials.
  • shows a diagram of how a spectrometer works.
  • When the spectrometer produces a reading, the observer can then use spectroscopy to identify the atoms and therefore molecules that make up that object.

• Mass

  • In theoretical physics, a mass generation mechanism is a theory which attempts to explain the origin of mass from the most fundamental laws of physics.
  • The physical property we are covering in this atom is called mass.
  • Weight is a different property of matter that, while related to mass, is not mass, but rather the amount of gravitational force acting on a given body of matter.
  • Mass is an intrinsic property that never changes.
  • The International System of Units (SI) measures mass in kilograms, or kg.

• Locating the Center of Mass

  • The center of mass is a statement of spatial arrangement of mass (i.e. distribution of mass within the system).
  • where M is the total mass in the volume.
  • If a continuous mass distribution has uniform density, which means ρ is constant, then the center of mass is the same as the center of the volume.
  • Thus, the center of mass of a circular cylinder of constant density has its center of mass on the axis of the cylinder.
  • Identify the center of mass for an object with continuous mass distribution

• Center of Gravity

  • This center of mass's main characteristic is that it appears to carry the whole mass of the body.
  • The center of mass does not actually carry all the mass, despite appearances.
  • Specifically: 'the total mass x the position of the center of mass= ∑ the mass of the individual particle x the position of the particle. ' The center of mass is a geometric point in three-dimensional volume.
  • where r is the reference axis x, y, or z; m is individual mass; ri is the individual position; and M is the total mass.
  • When taking the center of mass of an oddly shaped object, it is helpful to break it down into smaller sections whose mass and properties are easier to evaluate, and then add the products of the individual masses and positions and divide by the total mass.

• Mass

  • Mass is the quantity of matter that an object contains, as measured by its resistance to acceleration.
  • Mass, specifically inertial mass, is a quantitative measure of an object's resistance to acceleration.
  • The SI unit of mass is the kilogram (kg).
  • The kilogram is defined as being equal to the mass of the International Prototype Kilogram (IPK), which is almost exactly equal to the mass of one liter of water.
  • A graph of the relative change in mass of selected kilogram prototypes.

• Weight of the Earth

  • Newton's law of universal gravitation states that every point mass in the universe attracts every other point mass with a force that is directly proportional to the product of their masses, and inversely proportional to the square of the distance between them.
  • In modern language, the law states the following: Every point mass attracts every single other point mass by a force pointing along the line intersecting both points.
  • where $F$ is the force between the masses, $G$ is the gravitational constant, $m_1$ is the first mass, $m_2$ is the second mass and $r$ is the distance between the centers of the masses.
  • The theorem tells us how different parts of the mass distribution affect the gravitational force measured at a point located a distance $r_0$ from the center of the mass distribution:
  • The portion of the mass that is located at radii $rmass enclosed within a sphere of radius $r_0$ was concentrated at the center of the mass distribution (as noted above).

• Gravitational Attraction of Spherical Bodies: A Uniform Sphere

  • That is, a mass $m$ within a spherically symmetric shell of mass $M$, will feel no net force (Statement 2 of Shell Theorem).
  • Only the mass of the sphere within the desired radius $M_{mass of the sphere inside $d$) is relevant, and can be considered as a point mass at the center of the sphere.
  • So, the gravitational force acting upon point mass $m$ is:
  • That is, the sphere's mass is uniformly distributed.)
  • which shows that mass $m$ feels a force that is linearly proportional to its distance, $d$, from the sphere's center of mass.