Half -life. Time for number of atoms to be reduced to one half Wave-nature of a particle

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  Half -life.
  

Time for number of atoms to be reduced to one half

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  Wave-nature of a particle
  

Electron diffraction

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  Particulate nature of electromagnetic radiation
  

Photoelectric effect

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  De Broglie wavelength
  

Wavelength of a particle which have momentum or motion

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  Pieces of evidence, photoelectric effect
  

Maximum energy of emitted electrons depends on frequency
Maximum energy of emitted electrons doesn`t dependent on intensity
Rate of emission of electrons dependents on intensity at constant frequency

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  Photoelectric effect
  

Emissions of electron from the metal surface when electromagnetic radiation is incident on the surface

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  Photon
  

Packet of energy of electromagnetic radiation

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  Radiation defection (activity != count rate)
  

Absorption in air before detector
Background radiation
Self-absorption in source
It is not sensitive in all directions

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  Radioactive
  

A radioactive nucleus is an unstable nucleus that emits EM radiation randomly and spontaneously

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  Decay constant
  

Probability of decay of a nucleus per unit time

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  Why Beta particles have range of energies
  

Emitted beta particle has to share the energy of the disintegration with the emitted antineutrino

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  Radioactive decay
  

Emission of particle by unstable nucleus that emit EM spontaneously

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  Binding energy
  

Minimum energy required to separate the nucleons to infinity

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  Random decay
  

Time at which a nucleus will decay cannot be predicted

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  Spontaneous decay
  

Decay of a nucleus not affected by environmental factors

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  Mass defect
  

Difference between mass of nucleus and mass of nucleons, where nucleons are separated to infinity

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  Work function
  

Minimum energy required for an electron to leave surface

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  How photon model of EM accounts for this phenomenon
  

Photons are packets of energy
Energy of photons depends on frequency
Electrons can only absorb a single photon
Emission only possible if photon energy is at least the work function