Nuclear & Particle physics

• What are the three constituents of an atom?

  Protons, neutrons, and electrons
• What is the nucleus of an atom formed of?

  Protons and neutrons
• What is the proton number denoted by?

  Z
• What is the nucleon number denoted by?

  A
• What does the nucleon number represent?

  Number of protons and neutrons
• What did Rutherford's scattering experiment demonstrate?

  The existence of a nucleus

  
• What model of the atom was disproved by Rutherford's experiment?

  Thomson's plum pudding model

  
• What did the results of Rutherford's experiment suggest about the atom?

  It is mostly empty space

  
• What does a large angle deflection of alpha particles suggest?

  The center of the atom is positively charged
• What does very few particles deflected back by more than 90° suggest?

  The nucleus is very small and dense
• What is thermionic emission?

  Emission of electrons from heated metal
• How can electrons be accelerated?

  Using electric and magnetic fields

  
• What is the purpose of an electron gun?

  To accelerate electrons
• What happens to electrons in an electron gun?

  They are released from the cathode
• What is the role of the anode in an electron gun?

  To accelerate electrons towards it
• What are the two types of particle accelerators?

  • Linear accelerator (LINAC)
  • Cyclotron
• How does a linear accelerator work?

  Uses alternating electric fields to accelerate particles
• What is the function of drift tubes in a linear accelerator?

  To progressively increase particle acceleration
• How does a cyclotron accelerate particles?

  Uses magnetic and alternating electric fields
• What happens to particles in a cyclotron as they reach the edge of the electrode?

  They are accelerated by the electric field
• What is the purpose of a velocity selector in a mass spectrometer?

  To allow only ions of specific speeds through

  
• How is the radius of the path of ions used in mass spectrometry?

  To determine mass-to-charge ratios
• What is the relationship between magnetic force and particle motion?

  Magnetic force is always perpendicular to motion
• What is the formula for the radius of a charged particle's circular path?

  r = $\frac{mv}{BQ}$
• What properties must be conserved during particle interactions?

  Charge, energy, and momentum
• How can you observe charged particles in a bubble chamber?

  By analyzing the trails of ionized particles
• What does the radius of curvature of tracks in a bubble chamber indicate?

  Characteristics of the observed particle
• What does a sudden stop in particle tracks indicate?

  Particles have collided
• What does a change in direction of particle tracks indicate?

  Particles have collided
• What is the de Broglie relation used for?

  To find the wavelength of particles
• What is the formula for de Broglie wavelength?

  $\lambda =$$\frac{h}{p}$
• What does the Planck constant represent in the de Broglie relation?

  It relates momentum and wavelength
• What does the shape of particle tracks indicate?

  Interactions of particles
• What does it indicate if particle tracks stop suddenly?

  Particles have collided
• What does it indicate if particle tracks abruptly change direction?

  Particles have collided
• What does it mean if tracks appear to come from nothing?

  Particles created from an uncharged particle
• What is the de Broglie relation used for?

  Finding the wavelength of particles
• What does the de Broglie relation state about momentum and wavelength?

  They are inversely proportional
• What is the formula for the de Broglie wavelength?

  $\lambda =$$\frac{h}{p}$
• What happens to the energy required as the de Broglie wavelength decreases?

  Higher energy is required