1 / 6

Mass and Energy

Mass and Energy. E=mc 2 and all that. MASS and REST MASS. In 1905 Einstein showed that the mass of a moving object, as measured by a stationary observer, increases as it approaches the speed of light.

cornella
Download Presentation

Mass and Energy

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Mass and Energy E=mc2 and all that

  2. MASS and REST MASS In 1905 Einstein showed that the mass of a moving object, as measured by a stationary observer, increases as it approaches the speed of light. This effect is important for fundamental particles which can be accelerated to very high velocities.Therefore we use the term rest mass (m0) of the particle to mean the mass of the particle when it is stationary ?

  3. The energy equivalence of mass • We can talk abou the rest mass and the rest energy of a particle interchangeably. • However the units are awkward because they are so small • It is convenient to have another unit for energy in particle physics

  4. Units of Energy ---------------------------------------------- A negatively charged electron is accelerated from a negative electrode towards a positive electrode and in doing so gains kinetic energy. The amount of kinetic energy it acquires ,just before it strikes the anode is called 1 electron volt. Potential difference of 1 volt ++++++++++++++++++++++++++ An electron volt is a tiny quantity of energy 1eV=1.60 x10-19J

  5. The mass equivalent of the electron is 8.20x10-14J Which is the same as 8.20x10-14÷ 1.60x 10-1 9 = 511099eV These more sensible numbers are often used directly in calculations.

  6. The unified atomic mass unit • The unified atomic mass unit (u) is defined as of the mass of a atom. • On this scale the normal hydrogen atom has a mass of 1.008. • The oxygen-16 atom is 15.995 etc • 1u = 1.661 x 10-27kg = 931.5MeV

More Related